Rabbits poops on couch

Question
I have had my my first pet rabbit since the beginning of July and have throughly enjoyed the experience of sharing my home with Wilbur.  

She has been potty trained since about the second or third week I have had her, and except for the few times she has had an accident outside of her littler box there have been very few problems.  

However, every time she hops on the couch to relax with me she ends up leaving a number of droppings by the time it is all said and done.

Is there something that I am doing wrong or anything I can do to help her?

ps. for what it is worth it is a black leather couch.

Answer
Well, that could mean several things.  One, it could mean she is really comfy and doesn't mind "letting loose."  Or she is one of those bunnies that just isn't very good about depositing their droppings in the designated location (the litterbox). As long as she isn't peeing on the couch it should be ok, you might want to put a towel down so it will be easy to dispose of the droppings after she is done.

They are easy to clean up, and it is just vegetable matter, but I can see where you would want to keep the couch clean.

I would have a towel or something on the couch myself, otherwise you'd have to train her to stay off the couch.

Kim