I have a climber too! Bindi jumps out of his xpen - he's 6 mos old and has been doing this for over a month now. Wehave to keep our bedroom door closed so he doesn't have free reign of the house. I wouldn't mind it so much, but he jumps onto my bed and pees on it. We put a pee pad out so he can use that, but he'd rather use our comforter.
This weekend I'm going to rig up something to cover the top of the xpen...it's large, so it'll take some thinking...anyone have any suggestions?