Unless it was the company (highly doubtful), anybody running a Morrowind mud would have some serious copyright issues.

That's not saying there isn't one. Good luck searching.

Well, if you are talking about system wise, rather than world-wise, DartMUD has a similar method of improving in a skill, customization is welcome, and people's suggestions are often implemented into the world.

Now, on the other hand, if you are talking about the world of Morrowind, I don't think you'll have too much luck there.