I built AbiWord on IRIX 6.5 a long time ago, and I _believe_ this problem
was that it was using the installed vendor version of libpng, which
was old or broken (or both). I used the libpng from our CVS archive
(or the one from the tarball) as a replacement and it worked fine.
In the mean time (to test this), try doing "./AbiWord -nosplash" and
see if it loads fine. If so, it's probably the libpng problem.
-- Shaw Terwilliger