Version:           2.1.1 (using KDE 4.7.1) 
OS:                Linux

If Nepomuk is running and Nepomuk usage is active in digiKam, the virtuoso-t and digikamnepomukservice processes use up a lot of cpu, but since they're nice'd it's not so bad and I usually leave them running.
At one point however, they almost blocked the system so I had to stop them (via KDE systemsettings, even though it took several minutes and I was about to -9 them).
Starting digiKam with Nepomuk deactivated led to a mess. The tags list is literally swarmed with hundreds of nepomuk:/res/…, additionally, all tags sub-categorized below others appear in the top tag list as well. This makes tags in digiKam basically useless.
The correct tags still exist and the images are tagged correctly, but tagging new images or even just filtering for existing tags becomes very tedious.
Restarting Nepomuk or switching Nepomuk usage in digiKam on or off has no effect.

Reproducible: Always

Steps to Reproduce:
1. Setup a new user account.
2. Copy or symlink a bunch of images (preferably original, unchanged raw images with no tags already written to them) to a place the user has access to. Make sure to not copy or link .xmp files if there are some.
3. Make sure Nepomuk is activated and running
4. Start digiKam, point it to the images and let it scan them
5. Activate Nepomuk usage in the digiKam settings
6. Tag the images, including nested tags
7. Exit digiKam and stop Nepomuk
8. Restart digiKam and look at the tag list

Actual Results:  
The tag list is filled with internal Nepomuk resource tags and duplicates of existing tags without their sub-category. It also makes the tag widget very sluggish.

Expected Results:  
No changes to the tag list should occur.

Question: Is there a way to repair or fix this without re-tagging all images? Or simply not show these additional tags?