XUL, SwiXML, & Thinlets

Our research group (http://friam.org) is looking into better tools for 
simulation work.  The UI in particular can be quite arduous.  The idea 
of using XML to describe the UI sounds great!  Some questions:

1 - XUL: I'm a bit confused by the difference between building XUL for 
Thinlets vs Spring.  Is it a goal that the XUL should be able to be 
targeted to multiple widget sets (AWT, Thinlets, Swing, SWT) and 
possibly even different languages (Java, Python, TclTK, ...) by 
supplying the "engine" that translates from the XUL to the target 
platform?

2 - Thinlets vs SwiXML: If the above is somewhat true, then the 
thinlets.jar provide the engine for the Thinlets widgets, and SwiXML 
provide a different engine for the swing widgets, right?

3 - Jython: Presumably one could access either the thinlets or swixml 
engines from Jython.  Is this possible?  Any idea how?

4 - Theodore: Can Theodore produce XUL that could be used by both the 
thinlets and swixml engines?

Thanks!

Owen    http://backspaces.net/