handling non cookied users when registering

I'm working on a registration hack that automaticly creates a new thread with a post, or just a post in a predefined thread in the users name, with a standard welcome, or one they can write themselves from the registration form.
The only issue I have remaining, when a person clicks on the activation link and does not have cookies, different browser, etc., the post shows up as guest. The codes I'm using for getting the user info for both the thread creation and post is

PHP Code:

".addslashes($userinfo[username])."','$bbuserinfo[userid]' 

Is there something else I can call to show those not having the site's cookies, when they click the activation email link, as registered in the post?

[ap0c]

bump... couldnt delete this thread, so I changed it