diff --git a/util/StrDefs.ct b/util/StrDefs.ct
index b597b2051..b682255ad 100644
--- a/util/StrDefs.ct
+++ b/util/StrDefs.ct
@@ -46,6 +46,8 @@ SOFTWARE.
 ******************************************************************/
 
 #define Const const
+#include "StringDefs.h"
+#include "Shell.h"
 
 <<<STRING_TABLE_GOES_HERE>>>
 
diff --git a/util/StrDefs.ht b/util/StrDefs.ht
index 2ce20562f..ceab2610f 100644
--- a/util/StrDefs.ht
+++ b/util/StrDefs.ht
@@ -52,6 +52,18 @@ SOFTWARE.
 #define _XtStringDefs_h_Const const
 #endif
 
+#ifndef XT_EXTERN_API
+# if defined(_MSC_VER) && defined(XT_DLL_EXPORTS)
+#  ifdef XT_BUILD
+#   define XT_EXTERN_API extern __declspec(dllexport)
+#  else
+#   define XT_EXTERN_API extern __declspec(dllimport)
+#  endif
+# else
+#  define XT_EXTERN_API extern
+# endif
+#endif
+
 <<<STRING_TABLE_GOES_HERE>>>
 
 #ifndef XTSTRINGDEFINES
diff --git a/util/string.list b/util/string.list
index 49ba7476e..753c592b3 100644
--- a/util/string.list
+++ b/util/string.list
@@ -6,7 +6,7 @@
 
 #prefix Xt
 #feature XTSTRINGDEFINES
-#externref extern
+#externref XT_EXTERN_API
 #externdef
 ! note that the trailing space is required in the #externdef line.
 #ctmpl util/StrDefs.ct
diff --git a/util/Shell.ht b/util/Shell.ht
index 500e0fd75..ac8fc2a2e 100644
--- a/util/Shell.ht
+++ b/util/Shell.ht
@@ -64,6 +64,18 @@ SOFTWARE.
 #define _XtShell_h_Const const
 #endif
 
+#ifndef XT_EXTERN_API
+# if defined(_MSC_VER) && defined(XT_DLL_EXPORTS)
+#  ifdef XT_BUILD
+#   define XT_EXTERN_API extern __declspec(dllexport)
+#  else
+#   define XT_EXTERN_API extern __declspec(dllimport)
+#  endif
+# else
+#  define XT_EXTERN_API extern
+# endif
+#endif
+
 <<<STRING_TABLE_GOES_HERE>>>
 
 #ifndef XTSTRINGDEFINES
diff --git a/include/X11/Intrinsic.h b/include/X11/Intrinsic.h
index 559697aa0..d11eb0955 100644
--- a/include/X11/Intrinsic.h
+++ b/include/X11/Intrinsic.h
@@ -106,7 +106,18 @@ typedef char *String;
 #define externalref globalref
 #define externaldef(psect) globaldef {"psect"} noshare
 #else
-#define externalref extern
+#ifndef XT_EXTERN_API
+# if defined(_MSC_VER) && defined(XT_DLL_EXPORTS)
+#  ifdef XT_BUILD
+#   define XT_EXTERN_API extern __declspec(dllexport)
+#  else
+#   define XT_EXTERN_API extern __declspec(dllimport)
+#  endif
+# else
+#  define XT_EXTERN_API extern
+# endif
+#endif
+#define externalref XT_EXTERN_API
 #define externaldef(psect)
 #endif /* VMS */