Well, my university's account for 6 continuous weeks
doesn't log me in, cause of the 619 error. I tried
installing XP in another fragment and the dial-up
connection worked fine for one week, then also fell to 619,
without been able to be restored with system restore.
From what I've read in the knowledge base, probably the
administrators in the University messed up with the active
directory. The problem is that
1)I am not sure whether that's the case - please suggest
other possible problems
2)I have to convince them to give me some minutes of their
time to correct their errors.

I still wonder why XP started fine and one nice day stopped
being able to make the connection.