Thread:Project:Support desk/Flag/Tag a Revsion/reply (6)

What you want to do could probably build on the FlaggedRevs extension although FR wouldn't work for you out of the box. As far as I know, there is no other extension that would do what you want.

If you do not have the means to do adapt FlaggedRevs to your needs by yourself, then you can file a bug or hire a consultant (disclosure: I work on MediaWiki contracts).