diff --git a/PCbuild/_sqlite3.vcproj b/PCbuild/_sqlite3.vcproj
index a0408a6..e0402f9 100644
--- a/PCbuild/_sqlite3.vcproj
+++ b/PCbuild/_sqlite3.vcproj
@@ -193,7 +193,7 @@
 			ATLMinimizesCRunTimeLibraryUsage="FALSE">
 			<Tool
 				Name="VCCLCompilerTool"
-				AdditionalOptions=" /USECL:MS_OPTERON"
+				AdditionalOptions=" /USECL:MS_OPTERON /GS-"
 				Optimization="2"
 				InlineFunctionExpansion="1"
 				AdditionalIncludeDirectories="..\Include;..\PC;..\..\sqlite-source-3.3.4"
diff --git a/PCbuild/_ssl.mak b/PCbuild/_ssl.mak
index 2623d27..5641c6a 100644
--- a/PCbuild/_ssl.mak
+++ b/PCbuild/_ssl.mak
@@ -31,7 +31,7 @@
 
 _hashlib$(SUFFIX): $(HASH_SOURCE) $(SSL_LIB_DIR)/libeay32.lib ../PC/*.h ../Include/*.h
     @if not exist "$(TEMP)/_hashlib/." mkdir "$(TEMP)/_hashlib"
-    cl /nologo /c $(HASH_SOURCE) $(CFLAGS) /Fo$(TEMP)\_hashlib\$*.obj $(INCLUDES) 
+    cl /nologo /c $(HASH_SOURCE) $(CFLAGS) $(EXTRA_CFLAGS) /Fo$(TEMP)\_hashlib\$*.obj $(INCLUDES) 
     link /nologo @<<
 	/dll /out:_hashlib$(SUFFIX) $(HASH_LIBS) $(TEMP)\_hashlib\$*.obj
 <<
diff --git a/PCbuild/build_ssl.py b/PCbuild/build_ssl.py
index 5ab3449..2a31ca4 100644
--- a/PCbuild/build_ssl.py
+++ b/PCbuild/build_ssl.py
@@ -169,6 +169,8 @@
     defs = "SSL_DIR=\"%s\"" % (ssl_dir,)
     if debug:
         defs = defs + " " + "DEBUG=1"
+    if arch in ('amd64', 'ia64'):
+        defs = defs + " EXTRA_CFLAGS=/GS-"
     makeCommand = 'nmake /nologo -f _ssl.mak ' + defs + " " + make_flags
     print "Executing:", makeCommand
     sys.stdout.flush()
diff --git a/PCbuild/pyexpat.vcproj b/PCbuild/pyexpat.vcproj
index c2b8824..2657e3b 100644
--- a/PCbuild/pyexpat.vcproj
+++ b/PCbuild/pyexpat.vcproj
@@ -189,7 +189,7 @@
 			ATLMinimizesCRunTimeLibraryUsage="FALSE">
 			<Tool
 				Name="VCCLCompilerTool"
-				AdditionalOptions=" /USECL:MS_OPTERON"
+				AdditionalOptions=" /USECL:MS_OPTERON  /GS-"
 				Optimization="2"
 				InlineFunctionExpansion="1"
 				AdditionalIncludeDirectories="..\Include,..\PC,..\Modules\expat"