Ubiquity should avoid partlocked error when rebuilding disk cache

I've noticed this on the quantal-20120924 image for both i386 and amd64
When selecting manual partitioning, and creating an encrypted volume, an error dialog box pops up after creating the partition. It does not inhibit installation, but the errors seem to stack when you create additional encrypted volumes. After creating the first one, I get this error once for the one I just created. Upon creating a second encrypted volume, I get the error message an additional 2 times for the first partition, and a 3rd time for the one I just created.

Here's the full text:

Partition in use
No modifications can be made to the partition #5 of device SCSI1 (0,0,0) (sda) for the following reasons:
In use as a physical volume for encrypted volume sda5_crypt

Screenshot attached.

ProblemType: Bug
DistroRelease: Ubuntu 12.10
Package: ubiquity 2.12.2
ProcVersionSignature: Ubuntu 3.5.0-15.22-generic 3.5.4
Uname: Linux 3.5.0-15-generic i686
ApportVersion: 2.5.2-0ubuntu4
Architecture: i386
CasperVersion: 1.324
Date: Mon Sep 24 21:38:59 2012
InstallCmdLine: file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd.lz quiet splash -- maybe-ubiquity
LiveMediaBuild: Ubuntu 12.10 "Quantal Quetzal" - Beta i386 (20120924)
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: ubiquity
UpgradeStatus: No upgrade log present (probably fresh install)