Because it's not Thursday after dark. If it were, the 0 would have been replaced with a jack and he'd be on the way to a royal fizzbin. Unless he got a kronk, but that'd just be bad luck.
I think the problem is that he doesn't understand his own spec well enough to either write the regex nor to explain it to us. It's probably time for the OP to sit down, go back to square one, and enumerate just what it is that's trying to be accomplished.