install status messages are graphically messed up when moused-over

[Joel Pickett]

Graphical artifact occurs when installing, the status bar, as seen in the pictures when you mouse of that line.

ProblemType: Bug
DistroRelease: Ubuntu 12.10
Package: ubiquity 2.12.8
ProcVersionSignature: Ubuntu 3.5.0-16.25-generic 3.5.4
Uname: Linux 3.5.0-16-generic x86_64
ApportVersion: 2.6.1-0ubuntu1
Architecture: amd64
CasperVersion: 1.327
Date: Thu Oct 4 23:54:31 2012
InstallCmdLine: initrd=/ubninit file=/cdrom/preseed/ubuntu.seed boot=casper quiet splash -- BOOT_IMAGE=/ubnkern
LiveMediaBuild: Ubuntu 12.10 "Quantal Quetzal" - Beta amd64 (20121004)
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: ubiquity
UpgradeStatus: No upgrade log present (probably fresh install)