gnome-panel crashed with SIGSEGV in g_signal_emit_valist()

I just logged out, tried gnome flashback, didn't like it. Went back to default and got this error upon login.

ProblemType: Crash
DistroRelease: Ubuntu 13.10
Package: gnome-panel 1:3.6.2-0ubuntu11
ProcVersionSignature: Ubuntu 3.9.0-7.15-generic 3.9.7
Uname: Linux 3.9.0-7-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.10.2-0ubuntu2
Architecture: amd64
Date: Thu Jun 27 09:50:41 2013
ExecutablePath: /usr/bin/gnome-panel
GsettingsChanges:

InstallationDate: Installed on 2011-11-23 (582 days ago)
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
MarkForUpload: True
ProcCmdline: gnome-panel
ProcEnviron:
 LANGUAGE=en_US
 PATH=(custom, user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SegvAnalysis:
 Segfault happened at: 0x7fd3c2341c18: mov 0x98(%rax),%edx
 PC (0x7fd3c2341c18) ok
 source "0x98(%rax)" (0xaaaaaaaaaaaaab42) not located in a known VMA region (needed readable region)!
 destination "%edx" ok
SegvReason: reading unknown VMA
Signal: 11
SourcePackage: gnome-panel
StacktraceTop:
 ?? () from /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
 ?? () from /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
 ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
 g_signal_emit_valist () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
 g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
Title: gnome-panel crashed with SIGSEGV in g_signal_emit_valist()
UpgradeStatus: Upgraded to saucy on 2013-06-26 (1 days ago)
UserGroups: adm admin audio cdrom dialout fuse lpadmin netdev plugdev sambashare video