Traceback (most recent call last):
  File "/usr/bin/trytond", line 30, in <module>
    trytond.server.TrytonServer().run()
  File "/usr/lib/python2.7/dist-packages/trytond/server.py", line 74, in run
    from trytond.backend import Database
  File "/usr/lib/python2.7/dist-packages/trytond/backend/__init__.py", line 10, in <module>
    from postgresql import *
  File "/usr/lib/python2.7/dist-packages/trytond/backend/postgresql/__init__.py", line 4, in <module>
    from database import *
  File "/usr/lib/python2.7/dist-packages/trytond/backend/postgresql/database.py", line 7, in <module>
    from psycopg2.pool import ThreadedConnectionPool
  File "/usr/lib/python2.7/dist-packages/psycopg2/__init__.py", line 69, in <module>
    from _psycopg import BINARY, NUMBER, STRING, DATETIME, ROWID
ImportError: can't import mx.DateTime module