This implies that you are compiling the sources yourself (with modification)? If so, have you seen the hang with a binary distribution of AS 809?

Yes, I get the hang both with the AS 809 binary distribution and with an out-of-the-box release source code build of perl-5.8.4. I found I could not get reliable stack traces from the AS 809 binary distribution after the hang. I have not tried building from AS 809 sources yet, perhaps I should -- though I trusted that any AS 809 win32 patches would have made it back into the main perl-5.8.4 source stream.