Our system converts special characters such as "<" and ">" into safe HTML before insertion into our database.
This is to prevent Users from accidentally (or on purpose) posting HTML on the site that could potentially be dangerous to other users or just "screw up" a chat room/forum.
If you've received an error message similar to "Error: Your QuickPost can not be longer than 255 Characters!" then you probably tried to add some text that included special characters which were converted into safe HTML. You receive this error because there is a limit on the characters that feature can handle and the safe HTML has bumped your text over the limit. i.e. The "<" character in safe HTML is converted to ">" (which is 4 characters instead of 1).