I run a private forum for Poker Affiliates and I got this message from one of my members today

This is what I get when I try and post on this board.
YOUR IP (XXX.XXX.XX.XX) IS BLACKLISTED AS THE MESSAGE YOU POSTED INCLUDE SPAM WORDS.

BLACKLIST WILL BE REMOVED AFTER 24 HOURS.
Is there any way to turn this off at my forum? or atleast change the words it considers spam?