I found back in
that on my Debian 3.0 (Woody) box, compiling nsxml with any
optimization at all made it fail. "-g -O0", and it worked ok. That
was with AOLserver 3.3+ad13. My failure mode looked kind of different
than yours, so I don't think
you have the same problem,
espeically since you seem pretty sure that nsxml is working ok. But I
figured it's worth mentioning...
Since Vinod says OpenACS head is known to work on OS X, I'd probably
try that and see if you get any different results... If yes, then you
know the problem your seeing is either in your OpenACS code or in
nsxml. If no, then you know something else on your system is broken.