Multiple errors with Python 2.2.2 on Linux when test script 
is run. Using either roundup-0.5.1 or roundup-0.5.2, 
$python ./run_tests produces:

EEEEEEEEEEEEEEEEEE.........E.........EE.........................E................E.
.
.
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======================================================================
ERROR: testAccessControls 
(test.test_security.PermissionTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "./test/test_security.py", line 78, in testAccessControls
    userid = self.db.user.lookup('admin')
  File "./roundup/backends/back_anydbm.py", line 1429, in 
lookup
    cldb.close()
  File "/usr/local/lib/python2.2/dumbdbm.py", line 146, in 
close
    self._commit()
  File "/usr/local/lib/python2.2/dumbdbm.py", line 63, in 
_commit
    try: _os.unlink(self._bakfile)
TypeError: coercing to Unicode: need string or buffer, 
NoneType found
.
.
.
FAILED (errors=23)

All errors are _os._bakfile based.