I have just tried Jython on my SL-6000 using Debian on Xqt and the standard jdk-1.1.8 from Blackdown with the Swing-for-Zaurus "swingZ.jar". It works nicely pointing the CLASSPATH to the "classes.zip" from jdk118, the "swingZ.jar" and the "jython.jar".
I tried and modified a demo program from the distribution (drawing math. curves) and everything went smoothly.
Now I'm obliged to learn seriously Python... :-(