Zauber, are you talking about your own avatar or another avatar?
I've had that blurry textures on my avatar happen in the past with various versons of Cool VL Viewer, and it always seems to resolve itself after a while (meaning several relogs and clear caches later). I don't know what causes it, but have seen it from time to time. My guess is that the texture is corrupted in the cache.
Once some texture gets cached in a corrupted form it seems like it is impossible to get rid of it without relogging. Personally I'd be happy if there was a way to tell the viewer that all the textures in the cache are bad and to start downloading them all over--without having to relog, of course.
That refresh other avatar has been a lifesaver in laggy sims, by the way. Thanks Henri!
oops. that was me, I mis-read the post and deleted my response as quickly as possible, but aparently not quickly enough.