If I'm remembering right... if you go into the persons profile, click on user lists and then put that person on ignore they can not post in your threads and you wont see anything they post and they wont be able to send you any pms.

here are some other threads about the ignore feature maybe your answersd will be somewhere in there....

http://forums.psychcentral.com/commu...r-changes.html

http://forums.psychcentral.com/commu...t-threads.html

http://forums.psychcentral.com/commu...e-options.html

http://forums.psychcentral.com/commu...lying-you.html

there may be other threads concerning this issue in this board.. these are just the ones I remember seeing.....