In my Django login I always rewrite a logged in users url to have their username in it. So if the username is "joe" I rewrite the url to be "joe.example.com". This works great except on IE8 for usernames with underscores like "joe_schmoe". IE8 won't login the users when the url is like: "joe_schmoe.example.com". In my settings file I have wildcard subdomains for example.com turned on.
Is this a bug in IE8 or django? How can I work around it other than removing all underscores from usernames?