wip/py-shtoom error

I get the following error with shtoom:


$ shtoom.py --ui=text
Traceback (most recent call last):
  File "/usr/pkg/bin/shtoom.py", line 20, in <module>
    main()
  File "/usr/pkg/bin/shtoom.py", line 11, in main
    from shtoom.app.phone import Phone
  File "/usr/pkg/lib/python2.6/site-packages/shtoom/app/phone.py", line 5,
in <module>
    from shtoom.app.interfaces import Application
  File "/usr/pkg/lib/python2.6/site-packages/shtoom/app/interfaces.py",
line 4, in <module>
    from twisted.python.components import Interface
ImportError: cannot import name Interface


Any way to resolve this?
Mayuresh.

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