The JVM won't load Swing classes but will load AWT classes.
The iRex SimpleButton is neither AWT nor Swing and has a bug in its font handling, don't get too attached to it.
The kit I've put together fully supports the various layout managers making putting the various widgets up on the screen easier. They also fully support the AWT event delegation model to handle UI interactions. I'll be bundling what I've got so far and posting them later today.
I've got a couple more to implement before I can get my port of Jarnal to start playing nice. Jarnal is Swing based but I'll be porting it over to my AWT kit bit by bit and post as it grows. I'm pretty impressed with how feature packed it is and I'm eager to have it as a tool. I just hope I can get it to run nicely on the roughly 32MB of heap available.