Firefox doesn't open after closing

Binary package hint: firefox

Hello, I have some problem with firefox, yesterday I updated many packages, firefox3.6 included
and now firefox doesn't run anymore, I found that if I delete the .mozilla folder (that is in my home
folder) firefox runs once, then when I close firefox and want to run again, it doesn run, so I have
to manually delete the .mozilla folder in order to have firefox running again... I had the same problem
with Ubuntu 9.10 since I have updated to firefox3.6

Now I'm using:
  * Ubuntu 10.04 beta1 (upgraded from alpha3)
  * Firefox 3.6+nobinonly+0ubuntu6
  * Gnome 2.29.92-0ubuntu2
  * Linux 2.6.32-17.26-generic

Hardware:
  * HP Pavillion dv6921la
      + AMD TurionX2 2.0GHz
      + 2GB RAM

ProblemType: Bug
Architecture: amd64
Date: Wed Mar 24 16:41:02 2010
DistroRelease: Ubuntu 10.04
FirefoxPackages:
 firefox 3.6+nobinonly-0ubuntu6
 firefox-gnome-support 3.6+nobinonly-0ubuntu6
 firefox-branding 3.6+nobinonly-0ubuntu6
 abroswer N/A
 abrowser-branding N/A
InstallationMedia: Ubuntu 10.04 "Lucid Lynx" - Alpha amd64 (20100224.1)
NonfreeKernelModules: nvidia
Package: firefox 3.6+nobinonly-0ubuntu6
ProcEnviron:
 LANG=es_PE.utf8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.32-17.26-generic 2.6.32.10+drm33.1
SourcePackage: firefox
Uname: Linux 2.6.32-17-generic x86_64