Not sure if this is a Twisted issue or a Jython issue or both, so I'll post both ways.  Using Jython 2.2 alpha, the latest.

Trying to import Twisted into Jython on Win XP I get:
TypeError:  unhashable instance 
With the following stacktrace:

Jython 2.2a1 on java1.4.2_03 (JIT: null)
Type "copyright", "credits" or "license" for more information.
>>> import twisted
Traceback (innermost last):
  File "<console>", line 1, in ?
  File "c:\R.and.D\Jython\Lib\site-packages\twisted\__init__.py", line 18, in ?
  File "c:\R.and.D\Jython\Lib\site-packages\zope\interface\__init__.py", line 54, in ?
  File "c:\R.and.D\Jython\Lib\site-packages\zope\interface\interface.py", line 802, in ?
  File "c:\R.and.D\Jython\Lib\site-packages\zope\interface\interface.py", line 418, in __in
it__
  File "c:\R.and.D\Jython\Lib\site-packages\zope\interface\interface.py", line 225, in __in
it__
  File "c:\R.and.D\Jython\Lib\weakref.py", line 147, in __init__
TypeError: unhashable instance
>>>

There is a prior issue that Jython doesn't recognize site-packages on Win XP, though this seems to be solved with:
   sitedirs = [prefix, makepath(prefix, "Lib", "site-packages")]


Can anybody in this list shed light on the problem?

Regards,

Stephen Nightingale.