Database lock problems when starting FTS++

Test case:
1) run `zeitgeist-daemon --replace`
2) make sure you don't see a critical message mentioned below

===

In some cases the fts database can lock up and Zeitgeist reports:

[... CRITICAL] file ext-fts.c: line 732: unexpected error: Error
calling StartServiceByName for org.gnome.zeitgeist.SimpleIndexer:
GDBus.Error:org.freedesktop.DBus.Error.Spawn.ChildExited: Process
/usr/lib/zeitgeist/zeitgeist-fts exited with status 21 (g-dbus-error-quark, 25)

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: zeitgeist 0.9.0-1
ProcVersionSignature: Ubuntu 3.2.0-23.36-generic 3.2.14
Uname: Linux 3.2.0-23-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.0.1-0ubuntu6
Architecture: amd64
Date: Fri Apr 27 13:53:46 2012
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Beta amd64+mac (20110901)
PackageArchitecture: all
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: zeitgeist
UpgradeStatus: Upgraded to precise on 2012-01-12 (105 days ago)