Can not install raring desktop with manual partitioning

Selecting manual partitioning to install the latest raring desktop fails to create partition table and therefore its impossible to continue with the installation.

Steps:
1. Start the installation
2. On the Installation type select Something else and click 'Continue'
3. Select the device to partition and click 'New Partition Table' on the next window of Installation type
4. Click 'Continue' on the 'Create new empty partition table on this device?' dialog
5. Here it could be noticed that the + sign is still grayed out and a new partition table can not be created.

Occurrs on VMs ( virtual machine manager based) with i386, amd64 and amd64+mac images.

On hardware (mac-mini 5.2), the step 4 above (Create new empty partition on the device) does not create a new partition but manually deleting the existing partitions enable the + sign in the partition tool and the installation could be continued from there.

ProblemType: Bug
DistroRelease: Ubuntu 13.04
Package: ubiquity 2.13.6
ProcVersionSignature: Ubuntu 3.7.0-4.12-generic 3.7.0-rc7
Uname: Linux 3.7.0-4-generic i686
ApportVersion: 2.6.3-0ubuntu2
Architecture: i386
CasperVersion: 1.330
Date: Tue Dec 4 10:58:50 2012
InstallCmdLine: file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd.lz quiet splash --
LiveMediaBuild: Ubuntu 13.04 "Raring Ringtail" - Alpha i386 (20121204)
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)