A plugin that many people waits for.

I was looking (and many people!) for a plugin that make something like this: many users can only post in a category, each one to a specific category. For exaple:

user01 -> category01
user02 -> category02
user03 -> category01, category03
admin -> all

I was looking for this 4 days (I can′t belive it!) and I found a plugin but I only have a lot of problems.

Is it possible that anybody make a plugin like this?
Bye, and sorry my english.
??