WxPerl Windows will probably crash too.

Perhaps "bug" is too strong a term. Let's call it an "incompatibility".

The problem as I understand it, is to with static data in XS modules on modules that were never designed to work with threads. I believe that it is impossible to correct this incompatibility from within threads.

It requires modules like Win32::GUI, Tk (perhaps WxPerl), and many others, be modified to become compatible with threads.

I have no experience of WxPerl, but I'd bet that the same techniques I use in Re: threads causing memory leak (No leak!) would work with it also.