I saw this on Sourceforge; seems like what you are looking for:

"Thinlet Contrib is a collection of example apps, addons, plugins,
tutorials, FAQs, how-tos and other goodies for the Thinlet XUL (XML UI
Language) toolkit.
Programming Language: Java, JavaScript, Python, Ruby."

http://sourceforge.net/projects/thinlet-contrib/

"ScriptableThinlet 0.9 (November 30 2004) is a LGPL extension of Thinlet
that allow to define actions in script code inside the thinlet XUL file,
for various script language (beanshell, javascript, groovy, python,
judoscript...)"

http://sjobic.club.fr/thinlet/scriptablethinlet/index.html