log-in window can be move

[Romanos Dodopoulos]

The log-in window can be moved if press over the "top panel" and move the mouse.
Under the login window, appears corrupted desktop and some of the opened windows of the user.

I am not sure if the log-in window is under lightdm. If not, sorry for the inconvenience.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: lightdm 1.1.1-0ubuntu3
ProcVersionSignature: Ubuntu 3.2.0-10.17-generic 3.2.1
Uname: Linux 3.2.0-10-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 1.91-0ubuntu1
Architecture: amd64
Date: Mon Jan 23 21:00:40 2012
ExecutablePath: /usr/sbin/lightdm
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Alpha amd64 (20111129.1)
ProcEnviron: PATH=(custom, no user)
SourcePackage: lightdm
UpgradeStatus: No upgrade log present (probably fresh install)