Limit the creation of tags I wish to create a taxonomy where the administrator users limit which terms can be tagged.  

Suppose I have a vocabulary containing the following terms:


Football
Golf
Snooker


I want the tag autocomplete to show the tags that can be used. If I typed "Foo", the autocomplete should show "Football"; if I typed "Basketball," the autocomplete would not show anything, the node would submit, but no term is created. 

Is this possible?
It looks like the Content Taxonomy modules provides the ability to do this.

Without this, you'd have to implement hook_nodeapi('presave') and remove terms that don't exist yet.

Not even Drupal 7 seems to allow this without a contrib module, even though it does have specific edit terms permission for each vocabulary. Strange.