cannot get my pants off

I have a photorealistic Steve skin. Every so often it starts to act up such that when i take off all clothing i am either all black from the waist down or i am wearing my tux pants and shoes. Usually what i do that fixes it is to change to a newbie skin and wear a different copy of the steve skin, discarding the offended copy. This time that does not work. I have even bought a fresh copy of the steve skin without any change. Then i bought some other skins and found the same problem. If i put on shorts, my skin shows right.
What can i do next to resolve the issue?

Have you tried clearing Cache (Edit > Network > Clear Cache) and relogging? You may have to rebake your avatar after the viewer loads SL and your avatar rezzes (Ctrl + Alt + R assuming you're on Windows). Rebaking your avatar is a bit like reloading or refreshing a web page - all the textures are requested from the asset server again.

The problem is common enough these days and it appears to be a glitch with the latest viewer. I found that doing this sorted it out although it seems it hasn't worked for other residents.