GNOME freezes after log-in for 70/80 seconds then defreezes

I upgraded from Edgy to Feisty and the process was OK.
Now GDM starts, I log-in, appears the light orange backgound of ubuntu and the process freezes, the mouse can be moved, and in the upper left corner of the screen a white rectangle is visibile. The system stays like this for 70/80 seconds. Then I can hear the session start music and the white rectangle becomes a window with the following message:

There has been an error starting the gnome settings daemon.

Some aspects, such as themes, sound or backgroung settings may not work correctly.

The last error message has been:

Did not receive a reply. Possible causes include: the remote application
did not send a reply, the message bus security policy blocked the reply,
the reply timeout expired, or the network connection was broken.

GNOME will try to start the setting daemon again at the next login.
>>>>>>

Or that's a translation by me, since I use the Italian version. What I tryed to solve this:

1) disable every starting application, such as network manager, battery monitor, evolution, ecc.
2) deleting every setting of gnome and letting it create the new setting files.
3) creating a new user andtrying loggin in with that new user

None of this worked, as you can read in my ubuntu forum thread about this damned problem:

http://ubuntuforums.org/showthread.php?p=2602229#post2602229

There you'll find some more informations about my problem. How can I solve this, please?