gui login problem

[Errol Sapir]

I cannot login with my name and password when the main login requst 
comes up when booting. If I go to "repair mode" I can login to kubbuntu 
when applying control-E. So the problem isn't one of an incorrect 
username or password. I also created another user and tried to go in 
that way, again no gui entry.
Thinking the problem could be solved by reinstalling (and as I have my 
home on a different partition), I reinstalled and formatted my Kubuntu 
root partition. After installing, the problem is still there.
My (limited) understanding is that the problem is with some definition 
in the home partition. Is that possible and if so what?
My next step seems to be to boot with a live CD, copy my home to another 
place (external disk or whatever) and the reinstall formatting 
everything. Before I do that I'd to hear suggestions on how to solve 
this without such a drastic step.
TIA
Errol