Geeklog Forums

I posted in the wrong place last time so here is my question again.

My site has a forum plugin installed, so that anyone who wants to sign up as a member can become one. But when they want to post something they can't login in the same dialogue as the post textbox. Geeklog.net forum's post dialogue is kinda similar. If you have an account and want to post under that account, you have to be already logged in before you click on the "post a new topic" or "reply to this topic" buttons.

What I have in mind, though, is somewhat similar to the comment interface of LiveJournal--does anyone know about what it looks like? Someone who is posting a comment, if he is not already logged in, is prompted for his username and password just above the text field. Is it possible to implement something similar for my Geeklog?

Thanks!