pooping on walls, up against anything

We have a 1 1/2 year old female jack. We live in a big city and she has been trained on paper and to go outside. she is not confused with either, she's happy to do her business when she's out and she uses the paper when she's home. The problem is when she poops she raises her backside and poops on the wall, when she's outside she'll go up against a fence, tree whatever she can find. I've talked to my vet and the breeder and both were at a loss. Can you offer any advice regarding this bizarre problem?
Thank you.

• Re: pooping on walls, up against anything Oct 29 (0)