Pacman Game Problem

One of my members is complaining when he plays pacman he gets logged out of the forum when he is done.
He is also getting this error message-

mySQL query error: SELECT * FROM games_session WHERE sessid= LIMIT 1

mySQL error: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'LIMIT 1' at line 1
mySQL error code:
Date: Thursday 24th of May 2007 01:42:37 PM

Any Ideas??

Thanks