My little Holly is a Houdini of a climber. When she was little, I found two things that worked. A small ex-pen with smooth plastic sides (nothing to get a grip on) or one with a lid. Here are links to both varieties:
Small Pet Playpen with Mat/Cover Use a shower curtain liner for the bottom so you don't have to buy the extra canvas.
Teacup Yorkie Dogs » Play pens: a way to contain your yorkie or Yorkshire terrier Scroll down to see the brown and white playpen. Holly could not escape this, it was barely big enough. Since she has outgrown the need I use two of the walls as makeshift gates to keep her from getting through the railing in the living room.
And a third type I just found
Amazon.com: Exercise Pens Mesh Top 4 foot x 4...
Google plastic playpen then click on images for lots of ideas, just look for something that won't allow a foot hold. Good luck!