Gnome Startup Problems

[pau]

Hi!

I recently began to have problems with GDM startup. When I login I get
the Ubuntu image with that curious sound, and the Session Manager
Proxy starts, but it gets stucked. Nothing else starts and the only
thing I can do is alt+cntrl+F2 and restart GDM from a terminal.

The only solution I've found so far is to login with a problem proof
GNOME session (one of the options on the start up menu of GDM). I can
login without any problems and I get a message saying that GNOME
startup scripts will not be loaded.

I am a newbie in Linux World, but it seems to me that the problem
might be in the startup scripts. Does anyone have a clue?

Thanks 

Pau