Poop in the potty--sort of

Well, Carter has put some poop in his potty. He wanted to sit on it with his diaper off, and when I took his diaper off he told me he had some poop. I told him there wasn't any in his diaper because I didn't see any. But, when he sat down on his potty seat the poop he already had fell in. He was super excited, though, since he thought he had pooped in his potty! We let him get an M&M for it hoping it would encourage more potty action.
Nothing more so far, though.I'm not pushing anything, since Graham is due to arrive in about 5-6 weeks. Diapers are just pretty easy, and I don't want to be trying to potty train one with a newborn.