Mod_python error: "PythonHandler index"

Traceback (most recent call last):

  File "/usr/lib/python2.4/site-packages/mod_python/apache.py", line 299, in HandlerDispatch
    result = object(req)

  File "index.py", line 156, in handler

  File "index.py", line 121, in process

  File "lib/dbg.py", line 177, in log

IOError: [Errno 122] Disk quota exceeded