Hello,
There is Kubuntu 8.04 KDE4 on a PC and it has been upgraded to the latest apt packages. Thunderbird 2 was installed from apt packages. A gmail account was setup but it fails to authenticate the password and returns a normal wrong password error. After wasting a lot of time rechecking and suspecting the keyboard, I setup the account in Kmail and it worked fine. So there appears to be a bug in that Thunderbird package.
I would also like to add that KDE4 does not allow editing of its menus and Kmail's icon which was missing from the 'Internet' sub-menu, could not be added manually. Some people on the net appear to have similar problems. Even creating a new application shortcut on the desktop as well as task bar is not possible with a right click as that option itself is missing. KDE4 is still a little 'nangu'.