Limiting term selection I have a few OG Groups and now I want to limit the taxonomy term selection for each group. For the first part I'm planning on checking if the user is a member of a certain group and then proceeding accordingly. So far, so good. The problem is, that I really have no idea how to actually limit the term selection. I tried something with the form api, but I just keep getting fatal errors when saving a node. 

So... Can you guys help me limit the term selection? Telling me what do I actually need to do would really help. Thanks.
There is OG Vocabulary module for D6 (and just a basic D7 port) that 


  "provides each Organic Group with its own vocabularies (i.e. taxonomy). This lets groups logically segregate their content into categories which make sense for them. This module is integrated with Token, Rules and Services modules." 
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