Update: If your X11 setup supports it (XFCE, metacity + xcompmgr, compiz, etc), the JNA shaped window demo now has window transparency.
Thanks to Romain Guy for some initial testing and VMWare for making experimental linux installations easier.
Update: BTW, the linux setup I used was ubuntu (after installing xubuntu packages to get xfce; should have started with xubuntu). Note that the transparency is similar to that on OS X and w32, i.e. a single alpha level for the entire window. Next up is to apply a per-pixel alpha mask, if I can scrounge up some samples of how to do it on each platform.
I added some features to JNA to facilitate working with the X11 visual lookups (it returns an array of structures), so a few more files got changed than just the examples jar. If you want the latest and greatest, you'll need to check out from CVS and do 'ant examples-jar'.
