'Continue' and 'Go Back' push buttons keep getting added in the partman ui for every 'Go Back' button press in the partition step during raring installations

[Para Siva]

For ever 'Go Back' button presses in the manual partitioning step during the raring installation a set of 'Go Back' and 'Continue' push buttons keeps getting added.

1. Start the installation (live session or otherwise)
2. Click continue on the Welcome screen
3. Click continue on Preparing to install Ubuntu
4. Select 'Something else' and click continue on the Installation type screen
5. Click New partition table
6. Click 'Go back' on 'Create new empty partition table on this device?' pop up dialog
7. Continue steps 5 & 6 and it could be noticed that 'Go back' and 'Continue' buttons keep getting added to the 'Create new empty partition table on this device?' dialog
Please see the attached image for a screen shot

ProblemType: Bug
DistroRelease: Ubuntu 13.04
Package: ubiquity 2.13.7
ProcVersionSignature: Ubuntu 3.7.0-7.15-generic 3.7.0
Uname: Linux 3.7.0-7-generic x86_64
ApportVersion: 2.7-0ubuntu2
Architecture: amd64
CasperVersion: 1.330
Date: Thu Jan 3 11:40:33 2013
InstallCmdLine: file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd.lz quiet splash -- maybe-ubiquity
LiveMediaBuild: Ubuntu 13.04 "Raring Ringtail" - Alpha amd64 (20130103)
MarkForUpload: True
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)

[Para Siva (psivaa)]

The screenshot is attached