Separator position between user list and channel switcher is not saved

How to reproduce:
1) Go to Settings > Preferences and set both channel switcher and user list to the same side and switcher type to tree.
2) Move separator between the two to preferred position
3) Restart xchat

Expected result:
Separator position should be restored to the position it was in when xchat was closed.

Actual result:
Separator position is forgotten between sessions.

ProblemType: Bug
DistroRelease: Ubuntu 12.10
Package: xchat 2.8.8-3ubuntu15
ProcVersionSignature: Ubuntu 3.5.0-26.40-generic 3.5.7.6
Uname: Linux 3.5.0-26-generic x86_64
NonfreeKernelModules: fglrx
ApportVersion: 2.6.1-0ubuntu10
Architecture: amd64
Date: Fri Mar 1 03:05:01 2013
InstallationDate: Installed on 2012-11-07 (113 days ago)
InstallationMedia: Ubuntu 12.04.1 LTS "Precise Pangolin" - Release amd64 (20120823.1)
MarkForUpload: True
SourcePackage: xchat
UpgradeStatus: Upgraded to quantal on 2012-12-11 (79 days ago)