How to pre-populate textarea?

I'm using webwiz forums and need to change the behaviour of filtering bad words to redirect to not_posted.asp if a bad word is found.

That's easily done but the problem is if the user clicks back hoping to edit the message, their draft/content is gone.

I can capture the strMessage (at the moment dumping this into a session variable), but how can I get the strMessage inserted back into the textarea?

Thanks
Dan