updated for version 7.3.712
Problem:    Nmake from VS2010 SP1 is not recognized.
Solution:   Add the version number. (Ken Takata)
diff --git a/src/Make_mvc.mak b/src/Make_mvc.mak
index 3ac2960..ef75193 100644
--- a/src/Make_mvc.mak
+++ b/src/Make_mvc.mak
@@ -407,6 +407,9 @@
 !if "$(_NMAKE_VER)" == "10.00.30319.01"
 MSVCVER = 10.0
 !endif
+!if "$(_NMAKE_VER)" == "10.00.40219.01"
+MSVCVER = 10.0
+!endif
 !if "$(_NMAKE_VER)" == "11.00.50727.1"
 MSVCVER = 11.0
 !endif