There's a common problem for Ubuntu users who have enabled the automatic connection. When you login manually, your password get stored somewhere and you don't need to retype it each time you start an application who needs it. But when you autologin, some applications require typing your password again. That's stupid, cause if I set up automatic connection, it was to avoid those repetitive password entries.
So, I don't know how is managed the password in Ubuntu, but please change it so that an automatic login does the same as a manual one.
Example : I installed Ubuntu on my mother's computer (and fought to do so). As she hates password and doesn't have a brilliant memory, I set up automatic login (by the way, Microsoft Windows® doesn't ask any password), and create two shortcuts on her desktop, Evolution and Firefox. She launches Evolution, and a silly keyring manager appears over her screen.
I've read forum to fix this, but the solution is removing the "login" entry in the Keyring manager, which, first, isn't very secure, but second, is too hard to change (as a newbie).
Notice there are other cases you get prompted for password in you set up automatic connection : Gnome-Do for me =/.
