An other common problem with XML::Parser is that an incompatible (static) version of expat also comes with some (old) versions of Apache. If this version is in the library search path before the proper one... BANG!
from the Axkit FAQ:
The usual cause is currently a conflict between differing versions of expat that are being loaded at the same time. This shouldn't happen if you install expat as a shared library before you compile expat, as it will detect an installed version during configure.
If you still get problems despite this, you might want to compile apache without expat. This is done with the following configure option:
./configure --disable-rule=EXPAT