diff --git a/configure/os/CONFIG_SITE.Common.vxWorksCommon b/configure/os/CONFIG_SITE.Common.vxWorksCommon
index b7c514895..e2a25df8c 100644
--- a/configure/os/CONFIG_SITE.Common.vxWorksCommon
+++ b/configure/os/CONFIG_SITE.Common.vxWorksCommon
@@ -15,6 +15,7 @@ VXWORKS_VERSION = 5.4
 #VXWORKS_VERSION = 6.1
 #VXWORKS_VERSION = 6.2
 #VXWORKS_VERSION = 6.3
+#VXWORKS_VERSION = 6.4
 
 
 # Sites may override the following path for a particular host