Dolphin Beta 8: Error when clicking on Category

When clicking on a group category (from the "Categories" section within homepage: http://demozzz.com/dolphin7b/m/groups/browse/category/Music+%5Band%5D+Cinema), I get:

Possible attack!!! All data has been collected and sent to the site owner for analysis.

*Tested on Online Demo using FireFox 3.5.3

Yeah, i just had the same

After i migrated articles from D6 installation, it created lots of same categories. So i had to delete same ones, after u press Delete or Disable it gives u that: Possible attack!!! All data has been collected and sent to the site owner for analysis.