firefox-3.1 crashed with signal 5 in gdk_x_error()

[Lorenco Trichardt]

Binary package hint: firefox-3.1

Selecting a new profile in the profile manager....
Have two profiles...
start ff3.1 with -ProfileManager select the other profile... it crashes. Start with new profile next time.

ProblemType: Crash
Architecture: i386
CrashCounter: 1
DistroRelease: /usr/bin/lsb_release:81: DeprecationWarning: the sets module is deprecated import sets Ubuntu 9.04
ExecutablePath: /usr/lib/firefox-3.1b3pre/firefox-3.1
Package: firefox-3.1 3.1~b3~hg20090205r23182+nobinonly-0ubuntu1
ProcCmdline: /usr/lib/firefox-3.1b3pre/firefox-3.1
ProcEnviron:
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
Signal: 5
SourcePackage: firefox-3.1
StacktraceTop:
 gdk_x_error (display=0xb7a0d000, error=0xbfacd5d8)
 _XError () from /usr/lib/libX11.so.6
 _XReply () from /usr/lib/libX11.so.6
 XGetWindowProperty () from /usr/lib/libX11.so.6
 ?? () from /usr/lib/xulrunner-1.9.1b3pre/libxul.so
Title: firefox-3.1 crashed with signal 5 in gdk_x_error()
Uname: Linux 2.6.28-8-generic i686
UserGroups: adm admin audio cdrom dialout fax kvm libvirtd lpadmin netdev plugdev sambashare scanner video