Comment 8 for bug 1016654

Maybe this should become a Wishlist item, then. This, at least, gets a working solution in place in the short term if anyone happens upon this thread. Yes, it can be modified to "break the script rules" but at least for 99% of the users it's just an enhancement to the usability of the field. Of course, it could be expanded (change colors on invalid input, pop up a message, etc.) but this is a quick and easy short term solution.