Tomboy crashes at startup when Tomboy applet is removed

Binary package hint: tomboy

Tomboy won't run and crashes when the Tomboy applet is not on the panel. Adding the applet solves the problem.
Here's the crash message:

** (tomboy:5558): WARNING **: The following assembly referenced from /usr/lib/tomboy/Tomboy.exe could not be loaded:
     Assembly: appindicator-sharp (assemblyref_index=14)
     Version: 0.1.0.0
     Public Key: bcae265d1c7ab4c2
The assembly was not found in the Global Assembly Cache, a path listed in the MONO_PATH environment variable, or in the location of the executing assembly (/usr/lib/tomboy/).

** (tomboy:5558): WARNING **: Could not load file or assembly 'appindicator-sharp, Version=0.1.0.0, Culture=neutral, PublicKeyToken=bcae265d1c7ab4c2' or one of its dependencies.

Unhandled Exception: System.TypeLoadException: A type load exception has occurred.
  at Tomboy.Tomboy.Main (System.String[] args) [0x00000]

ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: tomboy 1.2.1-1ubuntu4
ProcVersionSignature: Ubuntu 2.6.35-5.6-generic 2.6.35-rc3
Uname: Linux 2.6.35-5-generic i686
Architecture: i386
Date: Mon Jun 28 15:23:38 2010
InstallationMedia: Ubuntu 10.04 "Lucid Lynx" - Beta i386 (20100318)
ProcEnviron:
 LANG=en_US.utf8
 SHELL=/bin/bash
SourcePackage: tomboy