FuriusMoonScreenlet.py crashed with GError in load_buttons(): El icono «gtk-close» no está presente en el tema

All the screenlets crash after login

ProblemType: Crash
DistroRelease: Ubuntu 11.10
Package: screenlets-pack-all 0.0.2-0ubuntu2
ProcVersionSignature: Ubuntu 3.0.0-11.18-generic 3.0.4
Uname: Linux 3.0.0-11-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 1.23-0ubuntu1
Architecture: amd64
Date: Wed Sep 14 23:13:39 2011
ExecutablePath: /usr/share/screenlets/screenlets-pack-all/FuriusMoon/FuriusMoonScreenlet.py
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Alpha amd64 (20100804)
InterpreterPath: /usr/bin/python2.7
PackageArchitecture: all
ProcCmdline: python -u /usr/share/screenlets/screenlets-pack-all/FuriusMoon/FuriusMoonScreenlet.py
ProcCwd: /home/perfe
ProcEnviron:
 PATH=(custom, user)
 LANG=es_ES.UTF-8
 SHELL=/bin/bash
PythonArgs: ['/usr/share/screenlets/screenlets-pack-all/FuriusMoon/FuriusMoonScreenlet.py']
SourcePackage: indiv-screenlets
Title: FuriusMoonScreenlet.py crashed with GError in load_buttons(): El icono «gtk-close» no está presente en el tema
Traceback:
 Traceback (most recent call last):
   File "/usr/lib/pymodules/python2.7/screenlets/__init__.py", line 1245, in load_buttons
     self.closeb = self.gtk_icon_theme.load_icon ("gtk-close", 16, 0)
 GError: El icono «gtk-close» no está presente en el tema
UpgradeStatus: Upgraded to oneiric on 2011-09-02 (12 days ago)
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