This kind of depends upon what key multiplexing software you use (assuming that you're a software multiboxer) and what you setup in your do-not-pass list. The best way that I've found is to just get in the habit of using the override key (defaults to PAUSE if using KeyClone) and then you can chat and type all you want. Otherwise, you end up either with the situation you describe (where it sounds like you may have added "/" to the do-not-pass list) or you have all of your characters saying the exact same thing every time (which can be kind of cool, but not so much when trying to chat/reply).