Hmm, you can have these problems pretty early on. Friends of ours had a baby a few years before we had DS1. She was changing her baby in the middle of the night, and he pooed during the change, and managed to spray the wall with poo.
As we didn't know a lot of people with tiny babies who talked to us about poo, we just thought this was normal, and put it on our list of what to expect.
We're pretty glad neither of our kids did that, though.