Annoying gap between Task Bar and the bottom of the screen

When I try to raise a window from taskbar I keep getting to this annoying situation! The problem is a 2 pixel gap between task bar and the bottom of the screen (which means that the taskbar is a bit HIGHER than the limit of how low I can move my mouse pointer), so whenever I click there - nothing happens.
It is possible to fix it by resizing lxpanel from 24 pixels (default) to 22 pixels.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: lubuntu-artwork 0.27
ProcVersionSignature: Ubuntu 3.2.0-24.37-generic 3.2.14
Uname: Linux 3.2.0-24-generic i686
ApportVersion: 2.0.1-0ubuntu6
Architecture: i386
Date: Fri Apr 27 21:29:47 2012
InstallationMedia: Lubuntu 12.04 "Precise Pangolin" - Release i386 (20120423)
PackageArchitecture: all
SourcePackage: lubuntu-artwork
UpgradeStatus: No upgrade log present (probably fresh install)