Registration page stating already existing... problems with IE8

My setup

I have a registration page that adds 'role1'. My autoassignrole (AAR) settings:

AAR: enabled
default user reg: yes
path: register/role1-path
title: set

I have user registration to be without email verification

I also have content profile with a couple fields showing on registration page

My Problem
If I am using IE8, I fill out my registration and hit create new account, it tells me:

-The name 'test' is already taken
-The email address test@asdf.com is already registered. Have you forgotten your password?

Basically, when you look at the logs, it creates the user and creates the content profile page. But give me an error saying it already exists.

This only happens in IE8. Chrome and FF3.5 seem to work just fine. This is kind of a big deal because it confuses the crap out of new users.

I am using head AAR.

Some extra notes:
I was using logintoboggan so I could delete non-verfied users after a while and I thought that was my problem at first... but uninstalling it doesnt fix anything.