Usertitles per Usergroup

[Andreas]

OK, right now you can define

> 50 Posts = Title X
> 200 Posts = Title Y
> 500 Posts = Title Z

You can also define that a usergroup should overwrite this with a fixed title.

But what if I want Usergroup ID 1 to have
> 50 Posts = Title X
> 200 Posts = Title Y
> 500 Posts = Title Z

and Usergroup Id 2
> 50 Posts = Title A
> 200 Posts = Title B
> 500 Posts = Title C

But that doesn't seem to be possible.
Any idea how this could be achieved?