diff --git a/build/pkgs/perl_term_readline_gnu/spkg-install b/build/pkgs/perl_term_readline_gnu/spkg-install
index f5ac8975a0e..ee637e431ff 100755
--- a/build/pkgs/perl_term_readline_gnu/spkg-install
+++ b/build/pkgs/perl_term_readline_gnu/spkg-install
@@ -8,5 +8,11 @@ fi
 
 cd src
 
-ARCHFLAGS='-arch x86_64' perl Makefile.PL --prefix=$SAGE_LOCAL INSTALL_BASE=$SAGE_LOCAL
+case `uname` in
+    Darwin )
+	ARCHFLAGS="-arch `uname -m`"
+	export ARCHFLAGS
+	;;
+esac
+perl Makefile.PL --prefix=$SAGE_LOCAL INSTALL_BASE=$SAGE_LOCAL
 $MAKE install