diff --git a/src/Make_mvc.mak b/src/Make_mvc.mak
index c2567d7..d738670 100644
--- a/src/Make_mvc.mak
+++ b/src/Make_mvc.mak
@@ -207,9 +207,9 @@
 
 !include <Win32.mak>
 
-# Turn on Win64 compatibility warnings for 32-bit compiler in VC8. (/Wp64 is
-# deprecated in VC9.)
-!if ("$(MSVCVER)" == "8.0") 
+# Turn on Win64 compatibility warnings for VC7.x and VC8.
+# (/Wp64 is deprecated in VC9 and generates an obnoxious warning.)
+!if ("$(MSVCVER)" == "7.0") || ("$(MSVCVER)" == "7.1") || ("$(MSVCVER)" == "8.0") 
 DEFINES=$(DEFINES) /Wp64
 !endif