diff --git a/nsprpub/TAG-INFO b/nsprpub/TAG-INFO
index 4cf11c329c1d..265294c920bb 100644
--- a/nsprpub/TAG-INFO
+++ b/nsprpub/TAG-INFO
@@ -1 +1 @@
-NSPR_4_10_2_RTM
+NSPR_4_10_3_BETA1
diff --git a/nsprpub/config/prdepend.h b/nsprpub/config/prdepend.h
index 6c66b37ca0fc..e49e92677e3e 100644
--- a/nsprpub/config/prdepend.h
+++ b/nsprpub/config/prdepend.h
@@ -10,4 +10,3 @@
  */
 
 #error "Do not include this header file."
-
diff --git a/nsprpub/configure b/nsprpub/configure
index 484a15a7d15f..433790b99319 100755
--- a/nsprpub/configure
+++ b/nsprpub/configure
@@ -736,7 +736,7 @@ test "$host_alias" != "$target_alias" &&
 
 MOD_MAJOR_VERSION=4
 MOD_MINOR_VERSION=10
-MOD_PATCH_VERSION=2
+MOD_PATCH_VERSION=3
 NSPR_MODNAME=nspr20
 _HAVE_PTHREADS=
 USE_PTHREADS=
@@ -3229,6 +3229,8 @@ fi
 
 
 
+MOZ_ALIGN=toolchain-default
+
 case "$target" in
 arm*-android*|arm*-linuxandroid*)
     MOZ_THUMB=yes
@@ -3236,6 +3238,7 @@ arm*-android*|arm*-linuxandroid*)
     MOZ_FPU=vfp
     MOZ_FLOAT_ABI=softfp
     MOZ_SOFT_FLOAT=yes
+    MOZ_ALIGN=no
     ;;
 arm*-*)
     if test -n "$MOZ_PLATFORM_MAEMO"; then
@@ -3338,14 +3341,14 @@ no)
     _SAVE_CFLAGS="$CFLAGS"
     CFLAGS="$arch_flag"
     cat > conftest.$ac_ext <<EOF
-#line 3342 "configure"
+#line 3345 "configure"
 #include "confdefs.h"
 
 int main() {
 return sizeof(__thumb2__);
 ; return 0; }
 EOF
-if { (eval echo configure:3349: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:3352: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   MOZ_THUMB2=1
 else
@@ -3402,21 +3405,61 @@ no)
     ;;
 esac
 
-all_flags=`echo $arch_flag $thumb_flag $thumb_interwork_flag $fpu_flag $float_abi_flag $soft_float_flag`
+case "$MOZ_ALIGN" in
+toolchain-default|"")
+    align_flag=""
+    ;;
+no)
+    align_flag="-mno-unaligned-access"
+    ;;
+yes)
+    align_flag="-munaligned-access"
+    ;;
+*)
+    align_flag=""
+    ;;
+esac
+
+if test -n "$align_flag"; then
+  _SAVE_CFLAGS="$CFLAGS"
+  CFLAGS="$CFLAGS $align_flag"
+  echo $ac_n "checking whether alignment flag ($align_flag) is supported""... $ac_c" 1>&6
+echo "configure:3428: checking whether alignment flag ($align_flag) is supported" >&5
+  cat > conftest.$ac_ext <<EOF
+#line 3430 "configure"
+#include "confdefs.h"
+
+int main() {
+
+; return 0; }
+EOF
+if { (eval echo configure:3437: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+  :
+else
+  echo "configure: failed program was:" >&5
+  cat conftest.$ac_ext >&5
+  rm -rf conftest*
+  align_flag=""
+fi
+rm -f conftest*
+  CFLAGS="$_SAVE_CFLAGS"
+fi
+
+all_flags=`echo $arch_flag $thumb_flag $thumb_interwork_flag $fpu_flag $float_abi_flag $soft_float_flag $align_flag`
 if test -n "$all_flags"; then
     _SAVE_CFLAGS="$CFLAGS"
     CFLAGS="$all_flags"
     echo $ac_n "checking whether the chosen combination of compiler flags ($all_flags) works""... $ac_c" 1>&6
-echo "configure:3411: checking whether the chosen combination of compiler flags ($all_flags) works" >&5
+echo "configure:3454: checking whether the chosen combination of compiler flags ($all_flags) works" >&5
     cat > conftest.$ac_ext <<EOF
-#line 3413 "configure"
+#line 3456 "configure"
 #include "confdefs.h"
 
 int main() {
 return 0;
 ; return 0; }
 EOF
-if { (eval echo configure:3420: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:3463: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   echo "$ac_t""yes" 1>&6
 else
@@ -3473,17 +3516,17 @@ EOF
     DSO_LDOPTS='-brtl -bnortllib -bM:SRE -bnoentry -bexpall -blibpath:/usr/lib:/lib'
     ac_safe=`echo "sys/atomic_op.h" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for sys/atomic_op.h""... $ac_c" 1>&6
-echo "configure:3477: checking for sys/atomic_op.h" >&5
+echo "configure:3520: checking for sys/atomic_op.h" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 3482 "configure"
+#line 3525 "configure"
 #include "confdefs.h"
 #include <sys/atomic_op.h>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:3487: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:3530: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -3640,7 +3683,7 @@ EOF
         _DEBUG_FLAGS='-gdwarf-2 -O0'
         MKSHLIB='$(CCC) $(DSO_LDOPTS) -o $@'
         echo $ac_n "checking for gethostbyaddr in -lbind""... $ac_c" 1>&6
-echo "configure:3644: checking for gethostbyaddr in -lbind" >&5
+echo "configure:3687: checking for gethostbyaddr in -lbind" >&5
 ac_lib_var=`echo bind'_'gethostbyaddr | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_lib_$ac_lib_var'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -3648,7 +3691,7 @@ else
   ac_save_LIBS="$LIBS"
 LIBS="-lbind  $LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 3652 "configure"
+#line 3695 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -3659,7 +3702,7 @@ int main() {
 gethostbyaddr()
 ; return 0; }
 EOF
-if { (eval echo configure:3663: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:3706: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_lib_$ac_lib_var=yes"
 else
@@ -3868,17 +3911,17 @@ EOF
     fi
     ac_safe=`echo "crt_externs.h" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for crt_externs.h""... $ac_c" 1>&6
-echo "configure:3872: checking for crt_externs.h" >&5
+echo "configure:3915: checking for crt_externs.h" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 3877 "configure"
+#line 3920 "configure"
 #include "confdefs.h"
 #include <crt_externs.h>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:3882: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:3925: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -4928,17 +4971,17 @@ EOF
         _OPTIMIZE_FLAGS="$_OPTIMIZE_FLAGS -Olimit 4000"
         ac_safe=`echo "machine/builtins.h" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for machine/builtins.h""... $ac_c" 1>&6
-echo "configure:4932: checking for machine/builtins.h" >&5
+echo "configure:4975: checking for machine/builtins.h" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 4937 "configure"
+#line 4980 "configure"
 #include "confdefs.h"
 #include <machine/builtins.h>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:4942: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:4985: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -5497,7 +5540,7 @@ case $target in
     ;;
 *)
     echo $ac_n "checking for dlopen in -ldl""... $ac_c" 1>&6
-echo "configure:5501: checking for dlopen in -ldl" >&5
+echo "configure:5544: checking for dlopen in -ldl" >&5
 ac_lib_var=`echo dl'_'dlopen | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_lib_$ac_lib_var'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -5505,7 +5548,7 @@ else
   ac_save_LIBS="$LIBS"
 LIBS="-ldl  $LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 5509 "configure"
+#line 5552 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -5516,7 +5559,7 @@ int main() {
 dlopen()
 ; return 0; }
 EOF
-if { (eval echo configure:5520: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:5563: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_lib_$ac_lib_var=yes"
 else
@@ -5533,17 +5576,17 @@ if eval "test \"`echo '$ac_cv_lib_'$ac_lib_var`\" = yes"; then
   echo "$ac_t""yes" 1>&6
   ac_safe=`echo "dlfcn.h" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for dlfcn.h""... $ac_c" 1>&6
-echo "configure:5537: checking for dlfcn.h" >&5
+echo "configure:5580: checking for dlfcn.h" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 5542 "configure"
+#line 5585 "configure"
 #include "confdefs.h"
 #include <dlfcn.h>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:5547: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:5590: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -5576,13 +5619,13 @@ esac
 
 if test $ac_cv_prog_gcc = yes; then
     echo $ac_n "checking whether ${CC-cc} needs -traditional""... $ac_c" 1>&6
-echo "configure:5580: checking whether ${CC-cc} needs -traditional" >&5
+echo "configure:5623: checking whether ${CC-cc} needs -traditional" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_gcc_traditional'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
     ac_pattern="Autoconf.*'x'"
   cat > conftest.$ac_ext <<EOF
-#line 5586 "configure"
+#line 5629 "configure"
 #include "confdefs.h"
 #include <sgtty.h>
 Autoconf TIOCGETP
@@ -5600,7 +5643,7 @@ rm -f conftest*
 
   if test $ac_cv_prog_gcc_traditional = no; then
     cat > conftest.$ac_ext <<EOF
-#line 5604 "configure"
+#line 5647 "configure"
 #include "confdefs.h"
 #include <termio.h>
 Autoconf TCGETA
@@ -5626,12 +5669,12 @@ LIBS="$LIBS $OS_LIBS"
 for ac_func in dladdr gettid lchown setpriority strerror syscall
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:5630: checking for $ac_func" >&5
+echo "configure:5673: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 5635 "configure"
+#line 5678 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -5654,7 +5697,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:5658: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:5701: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -5706,7 +5749,7 @@ do
 # Extract the first word of "$ac_prog", so it can be a program name with args.
 set dummy $ac_prog; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:5710: checking for $ac_word" >&5
+echo "configure:5753: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_path_CCACHE'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -5765,7 +5808,7 @@ hpux*)
 if test -z "$GNU_CC"; then
 
     echo $ac_n "checking for +Olit support""... $ac_c" 1>&6
-echo "configure:5769: checking for +Olit support" >&5
+echo "configure:5812: checking for +Olit support" >&5
 if eval "test \"`echo '$''{'ac_cv_hpux_usable_olit_option'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -5807,7 +5850,7 @@ wince*)
 *)
     
 echo $ac_n "checking for pthread_create in -lpthreads""... $ac_c" 1>&6
-echo "configure:5811: checking for pthread_create in -lpthreads" >&5
+echo "configure:5854: checking for pthread_create in -lpthreads" >&5
 echo "
     #include <pthread.h> 
     void *foo(void *v) { return v; } 
@@ -5829,7 +5872,7 @@ echo "
         echo "$ac_t""no" 1>&6
         
 echo $ac_n "checking for pthread_create in -lpthread""... $ac_c" 1>&6
-echo "configure:5833: checking for pthread_create in -lpthread" >&5
+echo "configure:5876: checking for pthread_create in -lpthread" >&5
 echo "
     #include <pthread.h> 
     void *foo(void *v) { return v; } 
@@ -5851,7 +5894,7 @@ echo "
         echo "$ac_t""no" 1>&6
         
 echo $ac_n "checking for pthread_create in -lc_r""... $ac_c" 1>&6
-echo "configure:5855: checking for pthread_create in -lc_r" >&5
+echo "configure:5898: checking for pthread_create in -lc_r" >&5
 echo "
     #include <pthread.h> 
     void *foo(void *v) { return v; } 
@@ -5873,7 +5916,7 @@ echo "
         echo "$ac_t""no" 1>&6
         
 echo $ac_n "checking for pthread_create in -lc""... $ac_c" 1>&6
-echo "configure:5877: checking for pthread_create in -lc" >&5
+echo "configure:5920: checking for pthread_create in -lc" >&5
 echo "
     #include <pthread.h> 
     void *foo(void *v) { return v; } 
@@ -5991,7 +6034,7 @@ if test -n "$USE_PTHREADS"; then
       rm -f conftest*
    ac_cv_have_dash_pthread=no
    echo $ac_n "checking whether ${CC-cc} accepts -pthread""... $ac_c" 1>&6
-echo "configure:5995: checking whether ${CC-cc} accepts -pthread" >&5
+echo "configure:6038: checking whether ${CC-cc} accepts -pthread" >&5
    echo 'int main() { return 0; }' | cat > conftest.c
    ${CC-cc} -pthread -o conftest conftest.c > conftest.out 2>&1
    if test $? -eq 0; then
@@ -6014,7 +6057,7 @@ echo "configure:5995: checking whether ${CC-cc} accepts -pthread" >&5
 			    ac_cv_have_dash_pthreads=no
     if test "$ac_cv_have_dash_pthread" = "no"; then
 	    echo $ac_n "checking whether ${CC-cc} accepts -pthreads""... $ac_c" 1>&6
-echo "configure:6018: checking whether ${CC-cc} accepts -pthreads" >&5
+echo "configure:6061: checking whether ${CC-cc} accepts -pthreads" >&5
     	echo 'int main() { return 0; }' | cat > conftest.c
 	    ${CC-cc} -pthreads -o conftest conftest.c > conftest.out 2>&1
     	if test $? -eq 0; then
diff --git a/nsprpub/configure.in b/nsprpub/configure.in
index 4b140c4e9db4..cc250a5cdf57 100644
--- a/nsprpub/configure.in
+++ b/nsprpub/configure.in
@@ -15,7 +15,7 @@ dnl = Defaults
 dnl ========================================================
 MOD_MAJOR_VERSION=4
 MOD_MINOR_VERSION=10
-MOD_PATCH_VERSION=2
+MOD_PATCH_VERSION=3
 NSPR_MODNAME=nspr20
 _HAVE_PTHREADS=
 USE_PTHREADS=
@@ -1006,6 +1006,8 @@ dnl = ARM toolchain tweaks
 dnl ========================================================
 
 dnl Defaults
+MOZ_ALIGN=toolchain-default
+
 case "$target" in
 arm*-android*|arm*-linuxandroid*)
     MOZ_THUMB=yes
@@ -1013,6 +1015,7 @@ arm*-android*|arm*-linuxandroid*)
     MOZ_FPU=vfp
     MOZ_FLOAT_ABI=softfp
     MOZ_SOFT_FLOAT=yes
+    MOZ_ALIGN=no
     ;;
 arm*-*)
     if test -n "$MOZ_PLATFORM_MAEMO"; then
@@ -1148,8 +1151,31 @@ no)
     ;;
 esac
 
+case "$MOZ_ALIGN" in
+toolchain-default|"")
+    align_flag=""
+    ;;
+no)
+    align_flag="-mno-unaligned-access"
+    ;;
+yes)
+    align_flag="-munaligned-access"
+    ;;
+*)
+    align_flag=""
+    ;;
+esac
+
+if test -n "$align_flag"; then
+  _SAVE_CFLAGS="$CFLAGS"
+  CFLAGS="$CFLAGS $align_flag"
+  AC_MSG_CHECKING(whether alignment flag ($align_flag) is supported)
+  AC_TRY_COMPILE([],[],,align_flag="")
+  CFLAGS="$_SAVE_CFLAGS"
+fi
+
 dnl Use echo to avoid accumulating space characters
-all_flags=`echo $arch_flag $thumb_flag $thumb_interwork_flag $fpu_flag $float_abi_flag $soft_float_flag`
+all_flags=`echo $arch_flag $thumb_flag $thumb_interwork_flag $fpu_flag $float_abi_flag $soft_float_flag $align_flag`
 if test -n "$all_flags"; then
     _SAVE_CFLAGS="$CFLAGS"
     CFLAGS="$all_flags"
diff --git a/nsprpub/pr/include/md/_unixos.h b/nsprpub/pr/include/md/_unixos.h
index 798d0b33d0e0..04d990414faf 100644
--- a/nsprpub/pr/include/md/_unixos.h
+++ b/nsprpub/pr/include/md/_unixos.h
@@ -493,6 +493,12 @@ extern PRStatus _MD_MemUnmap(void *addr, PRUint32 size);
 extern PRStatus _MD_CloseFileMap(struct PRFileMap *fmap);
 #define _MD_CLOSE_FILE_MAP _MD_CloseFileMap
 
+extern PRStatus _MD_SyncMemMap(
+    PRFileDesc *fd,
+    void *addr,
+    PRUint32 len);
+#define _MD_SYNC_MEM_MAP _MD_SyncMemMap
+
 /*
  * The standard (XPG4) gettimeofday() (from BSD) takes two arguments.
  * On some SVR4 derivatives, gettimeofday() takes only one argument.
diff --git a/nsprpub/pr/include/md/_win95.h b/nsprpub/pr/include/md/_win95.h
index b008c13237cd..d65e26437664 100644
--- a/nsprpub/pr/include/md/_win95.h
+++ b/nsprpub/pr/include/md/_win95.h
@@ -527,6 +527,12 @@ extern PRStatus _MD_MemUnmap(void *addr, PRUint32 size);
 extern PRStatus _MD_CloseFileMap(struct PRFileMap *fmap);
 #define _MD_CLOSE_FILE_MAP _MD_CloseFileMap
 
+extern PRStatus _MD_SyncMemMap(
+    PRFileDesc *fd,
+    void *addr,
+    PRUint32 len);
+#define _MD_SYNC_MEM_MAP _MD_SyncMemMap
+
 /* --- Named semaphores stuff --- */
 #define _PR_HAVE_NAMED_SEMAPHORES
 #define _MD_OPEN_SEMAPHORE            _PR_MD_OPEN_SEMAPHORE
diff --git a/nsprpub/pr/include/md/_winnt.h b/nsprpub/pr/include/md/_winnt.h
index 4d4d2c12709d..7e5477fdbe38 100644
--- a/nsprpub/pr/include/md/_winnt.h
+++ b/nsprpub/pr/include/md/_winnt.h
@@ -582,6 +582,12 @@ extern PRStatus _MD_MemUnmap(void *addr, PRUint32 size);
 extern PRStatus _MD_CloseFileMap(struct PRFileMap *fmap);
 #define _MD_CLOSE_FILE_MAP _MD_CloseFileMap
 
+extern PRStatus _MD_SyncMemMap(
+    PRFileDesc *fd,
+    void *addr,
+    PRUint32 len);
+#define _MD_SYNC_MEM_MAP _MD_SyncMemMap
+
 /* --- Named semaphores stuff --- */
 #define _PR_HAVE_NAMED_SEMAPHORES
 #define _MD_OPEN_SEMAPHORE            _PR_MD_OPEN_SEMAPHORE
diff --git a/nsprpub/pr/include/prinit.h b/nsprpub/pr/include/prinit.h
index 557f2e2202b4..111db078f185 100644
--- a/nsprpub/pr/include/prinit.h
+++ b/nsprpub/pr/include/prinit.h
@@ -31,11 +31,11 @@ PR_BEGIN_EXTERN_C
 ** The format of the version string is
 **     "<major version>.<minor version>[.<patch level>] [<Beta>]"
 */
-#define PR_VERSION  "4.10.2"
+#define PR_VERSION  "4.10.3 Beta"
 #define PR_VMAJOR   4
 #define PR_VMINOR   10
-#define PR_VPATCH   2
-#define PR_BETA     PR_FALSE
+#define PR_VPATCH   3
+#define PR_BETA     PR_TRUE
 
 /*
 ** PRVersionCheck
diff --git a/nsprpub/pr/include/prio.h b/nsprpub/pr/include/prio.h
index ac4b270dea47..afea88e9a846 100644
--- a/nsprpub/pr/include/prio.h
+++ b/nsprpub/pr/include/prio.h
@@ -1854,6 +1854,15 @@ NSPR_API(PRStatus) PR_MemUnmap(void *addr, PRUint32 len);
 
 NSPR_API(PRStatus) PR_CloseFileMap(PRFileMap *fmap);
 
+/*
+ * Synchronously flush the given memory-mapped address range of the given open
+ * file to disk.
+ */
+NSPR_API(PRStatus) PR_SyncMemMap(
+    PRFileDesc *fd,
+    void *addr,
+    PRUint32 len);
+
 /*
  ******************************************************************
  *
diff --git a/nsprpub/pr/include/private/primpl.h b/nsprpub/pr/include/private/primpl.h
index 5b5469c4f4b8..249f6caa4683 100644
--- a/nsprpub/pr/include/private/primpl.h
+++ b/nsprpub/pr/include/private/primpl.h
@@ -1974,6 +1974,12 @@ extern PRStatus _PR_MD_MEM_UNMAP(void *addr, PRUint32 size);
 extern PRStatus _PR_MD_CLOSE_FILE_MAP(PRFileMap *fmap);
 #define _PR_MD_CLOSE_FILE_MAP _MD_CLOSE_FILE_MAP
 
+extern PRStatus _PR_MD_SYNC_MEM_MAP(
+    PRFileDesc *fd,
+    void *addr,
+    PRUint32 len);
+#define _PR_MD_SYNC_MEM_MAP _MD_SYNC_MEM_MAP
+
 /* Named Shared Memory */
 
 /*
diff --git a/nsprpub/pr/src/io/prmmap.c b/nsprpub/pr/src/io/prmmap.c
index d22ba399fe29..6ffc133056b5 100644
--- a/nsprpub/pr/src/io/prmmap.c
+++ b/nsprpub/pr/src/io/prmmap.c
@@ -59,3 +59,11 @@ PR_IMPLEMENT(PRStatus) PR_CloseFileMap(PRFileMap *fmap)
 {
     return _PR_MD_CLOSE_FILE_MAP(fmap);
 }
+
+PR_IMPLEMENT(PRStatus) PR_SyncMemMap(
+    PRFileDesc *fd,
+    void *addr,
+    PRUint32 len)
+{
+  return _PR_MD_SYNC_MEM_MAP(fd, addr, len);
+}
diff --git a/nsprpub/pr/src/md/unix/unix.c b/nsprpub/pr/src/md/unix/unix.c
index 02962e6737a3..a3445a5f8fb2 100644
--- a/nsprpub/pr/src/md/unix/unix.c
+++ b/nsprpub/pr/src/md/unix/unix.c
@@ -3638,6 +3638,23 @@ PRStatus _MD_CloseFileMap(PRFileMap *fmap)
     return PR_SUCCESS;
 }
 
+PRStatus _MD_SyncMemMap(
+    PRFileDesc *fd,
+    void *addr,
+    PRUint32 len)
+{
+    if (msync(addr, len, MS_SYNC) == 0) {
+        return PR_SUCCESS;
+    } else {
+        if (errno == EINVAL) {
+            PR_SetError(PR_INVALID_ARGUMENT_ERROR, errno);
+        } else {
+            PR_SetError(PR_UNKNOWN_ERROR, errno);
+        }
+        return PR_FAILURE;
+    }
+}
+
 #if defined(_PR_NEED_FAKE_POLL)
 
 /*
diff --git a/nsprpub/pr/src/md/windows/ntmisc.c b/nsprpub/pr/src/md/windows/ntmisc.c
index e23f6725e977..7bd40b55156f 100644
--- a/nsprpub/pr/src/md/windows/ntmisc.c
+++ b/nsprpub/pr/src/md/windows/ntmisc.c
@@ -995,6 +995,23 @@ PRStatus _MD_CloseFileMap(PRFileMap *fmap)
     return PR_SUCCESS;
 }
 
+PRStatus _MD_SyncMemMap(
+    PRFileDesc *fd,
+    void *addr,
+    PRUint32 len)
+{
+    PROsfd osfd;
+
+    osfd = ( fd == (PRFileDesc*)-1 )?  -1 : fd->secret->md.osfd;
+
+    if (FlushViewOfFile(addr, len) && FlushFileBuffers((HANDLE) osfd)) {
+        return PR_SUCCESS;
+    } else {
+        PR_SetError(PR_UNKNOWN_ERROR, GetLastError());
+        return PR_FAILURE;
+    }
+}
+
 /*
  ***********************************************************************
  *
diff --git a/nsprpub/pr/src/nspr.def b/nsprpub/pr/src/nspr.def
index 7777a3dbe337..1639b97e0ff1 100644
--- a/nsprpub/pr/src/nspr.def
+++ b/nsprpub/pr/src/nspr.def
@@ -229,6 +229,7 @@ EXPORTS ;-
 		PR_Malloc;
 		PR_MemMap;
 		PR_MemUnmap;
+		PR_SyncMemMap;
 		PR_MicrosecondsToInterval;
 		PR_MillisecondsToInterval;
 		PR_LockOrderedLock;
diff --git a/nsprpub/pr/src/pthreads/ptthread.c b/nsprpub/pr/src/pthreads/ptthread.c
index 764ec2c88a8d..2a710ef5bf2c 100644
--- a/nsprpub/pr/src/pthreads/ptthread.c
+++ b/nsprpub/pr/src/pthreads/ptthread.c
@@ -52,6 +52,7 @@ static struct _PT_Bookeeping
     PRInt32 system, user;       /* a count of the two different types */
     PRUintn this_many;          /* number of threads allowed for exit */
     pthread_key_t key;          /* thread private data key */
+    PRBool keyCreated;          /* whether 'key' should be deleted */
     PRThread *first, *last;     /* list of threads we know about */
 #if defined(_PR_DCETHREADS) || defined(_POSIX_THREAD_PRIORITY_SCHEDULING)
     PRInt32 minPrio, maxPrio;   /* range of scheduling priorities */
@@ -979,9 +980,10 @@ void _PR_InitThreads(
      * nothing.
      */
     rv = _PT_PTHREAD_KEY_CREATE(&pt_book.key, _pt_thread_death);
-    PR_ASSERT(0 == rv);
+    if (0 != rv) PR_Abort();
+    pt_book.keyCreated = PR_TRUE;
     rv = pthread_setspecific(pt_book.key, thred);
-    PR_ASSERT(0 == rv);    
+    if (0 != rv) PR_Abort();
 }  /* _PR_InitThreads */
 
 #ifdef __GNUC__
@@ -1041,7 +1043,16 @@ void _PR_Fini(void)
     void *thred;
     int rv;
 
-    if (!_pr_initialized) return;
+    if (!_pr_initialized) {
+        /* Either NSPR was never successfully initialized or 
+         * PR_Cleanup has been called already. */
+        if (pt_book.keyCreated)
+        {
+            pthread_key_delete(pt_book.key);
+            pt_book.keyCreated = PR_FALSE;
+        }
+        return;
+    }
 
     _PT_PTHREAD_GETSPECIFIC(pt_book.key, thred);
     if (NULL != thred)
diff --git a/nsprpub/pr/tests/vercheck.c b/nsprpub/pr/tests/vercheck.c
index 6cfe137474e6..fef03529bb3c 100644
--- a/nsprpub/pr/tests/vercheck.c
+++ b/nsprpub/pr/tests/vercheck.c
@@ -20,9 +20,9 @@
 #include <stdlib.h>
 
 /*
- * This release (4.10.2) is backward compatible with the
+ * This release (4.10.3) is backward compatible with the
  * 4.0.x, 4.1.x, 4.2.x, 4.3.x, 4.4.x, 4.5.x, 4.6.x, 4.7.x,
- * 4.8.x, 4.9.x, 4.10, and 4.10.1 releases.
+ * 4.8.x, 4.9.x, 4.10, 4.10.1 and 4.10.2 releases.
  * It, of course, is compatible with itself.
  */
 static char *compatible_version[] = {
@@ -37,7 +37,7 @@ static char *compatible_version[] = {
     "4.8.6", "4.8.7", "4.8.8", "4.8.9",
     "4.9", "4.9.1", "4.9.2", "4.9.3", "4.9.4", "4.9.5",
     "4.9.6",
-    "4.10", "4.10.1",
+    "4.10", "4.10.1", "4.10.2",
     PR_VERSION
 };
 
@@ -53,7 +53,7 @@ static char *incompatible_version[] = {
     "3.0", "3.0.1",
     "3.1", "3.1.1", "3.1.2", "3.1.3",
     "3.5", "3.5.1",
-    "4.10.3",
+    "4.10.4",
     "4.11", "4.11.1",
     "10.0", "11.1", "12.14.20"
 };