Here's an ebuild for gprolog. Gprolog is a GNU implementation of prolog. It is very useful in the research and artifical intelligence fields. At the very least, it helps one understand make better (or vice versa). I suggest dev-langs/gprolog.
Please ignore the email I sent (with the ebuild file). It's broken. I'll upload a new ebuild shortly.
Can you whip up a new tarball and attach to this bug, if you're still interested in helping out with an ebuild for gprolog ? Sorry that this took so long.
Okay. I didn't get any response on this one, so I'm marking as invalid for now. Please reopen with your ebuild as an attachment if you're still around.