I created a parser for PDDL in Prolog. If you find it useful you can
download it here: http://artax.karlin.mff.cuni.cz/~sasar5am/pddl/
Feel free to comment it.
Robert Sasak
Here you can find related discussion:
http://groups.google.com/group/comp.lang.prolog/browse_thread/thread/4106e904e86fafe2