We are currently planning this feature.
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are sub-categories will be also available on the community edition?
I don't want to be anal but I found this http://www.opendocman.com/forum/viewtopic.php?f=4&t=641&p=1667&hilit=sub+category#p1674 and it says "I am sure we will be working on this once 1.2.6 goes final." and you've already released 184.108.40.206 ...
is this feature already on your development roadmap? if so, wha's the ETA?