[wlug] waikato imap

hey guys, I'm new at the UoW and also at this mailinglist ;) If someone is interested in this: I'm from Germany, 22 years old, using archlinux and (at my workstation at home) gentoo. So this is my first question: I've tried to setup an imap account for my university address at thunderbird. But everytime I trying to connect to imap.gmail.com i get the message "Invalid credentials (Failure)". While searching in google for a solution I can only find the notice to activate IMAP at webmail. That was the first thing i've done. Does anyone know something about this behaviour? or how to setup the imap-account correctly? Thanx and greatz, Ivo