unity bar doesnt adept when switching to bigger monitor

[Redmar]

When I switch from my 10.1 inch netbook to an external monitor, the unity bar remains the same (small) size, and doesn't adapt to the bigger screen, see the attached screenshot.

How to reproduce:
-Log into unity on the smaller screen.
-Switch to a bigger screen
-Observer how the unity bar is still the same size, and doesn't expand to the full size of the new monitor.

Temporary fix:
Press alt+f2 and run
unity --replace

to restart unity, after the restart unity will know its on a bigger monitor and draw the left bar accordingly.

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: unity 4.24.0-0ubuntu2b1
ProcVersionSignature: Ubuntu 3.0.0-12.20-generic 3.0.4
Uname: Linux 3.0.0-12-generic i686
ApportVersion: 1.23-0ubuntu3
Architecture: i386
CompizPlugins: [core,bailer,detection,composite,opengl,decor,regex,imgpng,animation,neg,resize,place,snap,session,move,unitymtgrabhandles,gnomecompat,workarounds,grid,vpswitch,compiztoolbox,mousepoll,expo,ezoom,wall,fade,scale,unityshell]
Date: Mon Oct 31 14:47:15 2011
DistroCodename: oneiric
DistroVariant: ubuntu
EcryptfsInUse: Yes
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release i386 (20111012)
ProcEnviron:
 PATH=(custom, no user)
 LANG=nl_NL.UTF-8
 SHELL=/bin/bash
SourcePackage: unity
UpgradeStatus: No upgrade log present (probably fresh install)