Why is there a blank white space under some Apps?

This seems to happen in any app that uses some kind of comment display thing. Here are some pictures. (sorry that they're not screenshots, I don't think it's possible without root) This also happens with every other Reddit app on the market. All of them have the exact same problem when viewing comments. I assume that there is some UI control in common between them, something that lists read-only tap-able text areas, but I'm not an Android developer so I don't actually know for sure. I'm using a Motorola Atrix 2 from AT&T with stock ROM.