Can't drag tags between categories

Binary package hint: hamster-applet

When I open the Hamster preferences screen and attempt to drag a Tag/Activity from the Unsorted category to any other category, nothing happens. When I drag the tag over the category, the category lights up like a valid drag target but when I release the mouse button the tag remains in the unsorted category.

TEST CASE:
1. Go to Edit/Preferences/Categories and Tags
2. In the list 'Categories' select 'Unsorted'
3. In the list 'Activities' add 3 activities ('Activity 01' to 'Activity 03') by clicking on '+' 3 times
4. Select a newly added activity (e.g 'Activity 02') and drag it to a Category (e.g 'Work')

VERIFICATION FAILED:
- When you drop the activity over the category, the activity remains on the same category

VERIFICATION SUCCEEDED:
- When you drop the activity over the category:
  - The activity is remove from the 'Unsorted' category and moved to the right category (e.g 'Work')

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: hamster-applet 2.30.0.1-0ubuntu1
ProcVersionSignature: Ubuntu 2.6.32-21.32-generic 2.6.32.11+drm33.2
Uname: Linux 2.6.32-21-generic i686
Architecture: i386
Date: Mon May 3 10:07:21 2010
ProcEnviron:
 PATH=(custom, user)
 LANG=en_US.utf8
 SHELL=bash
SourcePackage: hamster-applet