MOD_PYTHON ERROR

ProcessId:      3661855
Interpreter:    'lampsrv17.epfl.ch'

ServerName:     'lampsrv17.epfl.ch'
DocumentRoot:   '/var/www/lampsvn.epfl.ch'

URI:            '/trac/michelou'
Location:       '/trac'
Directory:      None
Filename:       '/var/www/lampsvn.epfl.ch/trac'
PathInfo:       '/michelou'

Phase:          'PythonHandler'
Handler:        'trac.web.modpython_frontend'

Traceback (most recent call last):

  File "/usr/lib/python2.7/dist-packages/mod_python/importer.py", line 1537, in HandlerDispatch
    default=default_handler, arg=req, silent=hlist.silent)

  File "/usr/lib/python2.7/dist-packages/mod_python/importer.py", line 1202, in _process_target
    module = import_module(module_name, path=path)

  File "/usr/lib/python2.7/dist-packages/mod_python/importer.py", line 304, in import_module
    return __import__(module_name, {}, {}, ['*'])

ImportError: No module named trac.web.modpython_frontend