diff --git a/HISTORY.TXT b/HISTORY.TXT
index fcd68d34c8..2d7851f8cd 100644
--- a/HISTORY.TXT
+++ b/HISTORY.TXT
@@ -13,6 +13,8 @@ For a complete change history, please see the Subversion log comments.
 
 Current Version:
 ----------------
+- Ensure the class is not marked BeforeFieldInit causing memory corruption with C#/CLR4 (#3438)
+
 - Fixed MSSQL2008 driver returning invalid extent (#3498)
 
 - Backport the recent fixes in the MSSQL2008 driver (#3058, #3244)
diff --git a/mapscript/csharp/Makefile.vc b/mapscript/csharp/Makefile.vc
index 99911b6651..4499eac815 100755
--- a/mapscript/csharp/Makefile.vc
+++ b/mapscript/csharp/Makefile.vc
@@ -48,7 +48,7 @@ CSC = csc $(CSDEBUG)
 !ENDIF
 
 !IF $(MSVC_VER) >= 1600
-CSC = $(CSC) /define:CLR4 /debug:full
+CSC = $(CSC) /define:CLR4
 !ENDIF
 
 #SWIG = swig
diff --git a/mapscript/csharp/swig_csharp_extensions.i b/mapscript/csharp/swig_csharp_extensions.i
index 54c9f99255..1d6e84be97 100644
--- a/mapscript/csharp/swig_csharp_extensions.i
+++ b/mapscript/csharp/swig_csharp_extensions.i
@@ -29,6 +29,12 @@
  * DEALINGS IN THE SOFTWARE.
  *****************************************************************************/
 
+// Ensure the class is not marked BeforeFieldInit causing memory corruption with CLR4 
+%pragma(csharp) imclasscode=%{
+  static $imclassname() {
+  }
+%}
+
 %typemap(csout, excode=SWIGEXCODE) SWIGTYPE {
     $&csclassname ret = new $&csclassname($imcall, true, null);$excode
     return ret;