Collaborative tags: what about user permissions?

Hi everyone!

Is it possible to forbid the changing or deleting tags for specific groups of users (as guests, for example)?
We use ā€œCollaborative Tagsā€ for fast searching among many shared files and if some stupid guy just will delete some tag -it will be a big problemā€¦
So is it possible to give different permissions to different groups?

Thank you!