Well, the jpeg plugin works exactly like the sql one. Just copy the jpeg dll (sorry don't know the right file name since I am now on my linux computer) to your executable (or in the subdirectory imageformats). It's a little bit confusing but a "Qt plugin" is an ordinary library. So you don't have to compile statically.

And the problem is, that the sdk dll's have build in png support but no jpeg. If you don't want do deliver also the jpeg plugin you can also rebuild Qt and activate build-in jpeg support (-qt-libjpeg).

EDIT: Ah, you get it to work! Then I was too late...