I did that, but it didn't solve my problem. What did solve my problem is reading further down the list of search results when searching these forums for "rundll32.exe". I have a ThinkPad T40 and it appears to be some kind of interaction between IBM's Battery Guage and Litestep, which isn't even displayed when using Litestep. So all I had to do was disable the Battery Guage (and add Battery to my handy-dandy label) to make the problem go away.

Thanks all.