I'd test it out. But instead of trying to send the user information out through another method I would try to use the users own post to get the information. You could possibly grab the cookie information and when the post button is click append that cookie information to the end of the users post inside an html comment. Then all you have to do is view the source of the users next post and see if the cookie information is there. If this is possibly you should notify the person who runs the board....they need to be parsing that crap out.