Pointing devices settings are not preserved after reboot

If I set 'GPointing Device Settings ▸ TPPS/2 IBM TrackPoint ▸ Wheel Emulation ▸ button' to '3', wheel emulation correctly uses button 3, the right mouse button. After rebooting and re-logging in, however, wheel emulation uses only button 2, the middle mouse button, despite the GPointing Device Settings GUI still displaying that button 3 is set. Temporarily changing 'button' to '2' and then back to '3' once again causes wheel emulation to use button 3 for the remainder of the login session.

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: gpointing-device-settings 1.5.1-5ubuntu1
ProcVersionSignature: Ubuntu 3.0.0-11.18-generic 3.0.4
Uname: Linux 3.0.0-11-generic x86_64
ApportVersion: 1.23-0ubuntu1
Architecture: amd64
Date: Fri Sep 23 11:46:57 2011
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Beta amd64 (20110413)
SourcePackage: gpointing-device-settings
UpgradeStatus: Upgraded to oneiric on 2011-09-23 (0 days ago)