Gedit tab width cannot be changed from combobox in status bar to a custom value

TEST CASE:
1) Open any document
2) Open Edit - Preferences menu
3) Go to Editor tab
4) Set Tab Width to any custom value (e.g. 1)
5) Close Preferences
6) Add a tab to any row in the document
Result: tab width is set to specified value (e.g. 1)
7) Change tab width to any predefined value using combobox in status bar (e.g. 4)
Result: tab width is set to selected value (4)
8) Change tab width to the custom value using combobox in status bar (last item, 1 in this example)

Result: tab width is not changed
Expected Result: tab width is changed to custom value

Note, that correct custom tab width value is set if user edits this in Preferences dialog

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: gedit 3.3.3-0ubuntu1
ProcVersionSignature: Ubuntu 3.2.0-14.23-generic-pae 3.2.3
Uname: Linux 3.2.0-14-generic-pae i686
ApportVersion: 1.91-0ubuntu1
Architecture: i386
Date: Wed Feb 8 13:17:37 2012
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Alpha i386 (20120201.1)
ProcEnviron:
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: gedit
UpgradeStatus: No upgrade log present (probably fresh install)