to be honest with you, no i don't have any solution for you. Because as i said, it is a very interesting situation.
Please do, create the same topic in the VM forum and enter its URL into this topic to help others people who are suffering from the same problem..
FYI: While creating topic in VM Forum, make sure to clearly declare that "You tried with/without VM template Override but the result is the same". So nobody would blame our template for this failure ;)
If Virtuemart Dev team notice your topic, they might fix this problem in the upcoming VM version. Or maybe somebody already has a patch for this problem. There are many VM geek hanging around in the VM forum.
regards