Jdk patch folder is not getting removed even after JDK uninstallation

Tested OS : windows
Tested Build : mustang jdk build b52 to b56

Steps to reproduce :

1. Install any mustang jdk build from b52 to b56
2. Go to C:\Program Files\Common Files\Java\Update\Base Images
Make sure jdk1.6.0.ea.b56 and jre1.6.0.ea.b56 folders exist
3. Uninstall jdk build
It can be noticed that jdk1.6.0.ea.b56 folder still exists under C:\Program Files\Common Files\Java\Update\Base Images even after jdk uninstallation
When you try to install JDK 6.0 b61 bundle, you will get the following error message
when it is installing JRE:

Error 1311. Source file not found: D:\Progrem Files\Common Files\Java\Update\Base Images\jdk1.6.0.ea.b56\patch-jdk1.6.0ea.b56\jo160000.cab. Verify that the file exists and that you can access it.

And build61 can not be installed sucessfully, also it will put the system
in a strange/dirty state. it needs to be fixed asap.