Credit where credit's due ... it was actually tye's observation that led to this solution.

I don't know what caused the original error. It's unusual for there to be 2 versions of Errno.pm in an ActivePerl installation. I still can't get a handle on how the problem has come about. At some stage during the 5.8.x releases ActiveState started putting their non-CORE (default) modules in perl/lib. Previously, those modules would have been in perl/site/lib. At the same time, they changed @INC to put perl/site/lib ahead of perl/lib. I think you must have done an upgrade during that "changeover" phase, and that's what's stuffed things up ... but I still can't get a handle on the exact nature of the problem ... and i wonder if there aren't other modules that are similarly affected.

Cheers,
Rob