Thank you, dasgar. That was exactly the problem.
In the meantime independently, I hit upon this advice:
https://groups.google.com/group/binary-wxperl/browse_thread/thread/f53be0143430f408?hl=en#
(see the answer, second post), (which is identical to what you're saying) and it fixed the problem. (Namely, removing some wx- related packages which originated from the ActiveState repository, and installing packages with the same name originating from the wxPerl repository).