--- gvpe/configure	2011/06/21 16:27:32	1.48
+++ gvpe/configure	2011/10/18 13:24:01	1.49
@@ -8579,7 +8579,7 @@
 
 
 cat >>confdefs.h <<_ACEOF
-#define MAX_MTU $MTU + 14
+#define MAX_MTU ($MTU + 14)
 _ACEOF