"Invisible" window controls on second monitor unexpectedly close window on first monitor

[Greg A]

Steps to reproduce:
1. Get a dual monitor setup (two monitors, side by side)
2. Maximise a window on the left monitor (for example Firefox)
3. Make sure the left hand window is focused
4. Move your mouse to the left of the panel on the right hand monitor
5. Click, and the window on the first monitor will close

Optional extra:
As well as maximising a window on the first monitor, maximise a window on the second monitor. If the first window is focused, you can still click on black space on the second monitor, and the window on the first monitor will close.

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: unity 4.24.0-0ubuntu2b1
ProcVersionSignature: Ubuntu 3.0.0-14.23-generic 3.0.9
Uname: Linux 3.0.0-14-generic x86_64
ApportVersion: 1.23-0ubuntu4
Architecture: amd64
CompizPlugins: [core,bailer,detection,composite,opengl,decor,compiztoolbox,imgpng,resize,place,snap,gnomecompat,vpswitch,move,grid,regex,animation,session,unitymtgrabhandles,mousepoll,workarounds,expo,wall,ezoom,fade,scale,unityshell]
Date: Sat Dec 10 08:26:06 2011
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Beta amd64 (20110901)
ProcEnviron:
 LANGUAGE=en_GB:en
 PATH=(custom, no user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: unity
UpgradeStatus: No upgrade log present (probably fresh install)