Mod_python error: "PythonHandler mod_python.publisher"

Traceback (most recent call last):

  File "/usr/lib/python2.4/site-packages/mod_python/apache.py", line 193, in Dispatch
    result = object(req)

  File "/usr/lib/python2.4/site-packages/mod_python/publisher.py", line 135, in handler
    module = apache.import_module(module_name, _req, [path])

  File "/usr/lib/python2.4/site-packages/mod_python/apache.py", line 332, in import_module
    f, p, d = imp.find_module(parts[i], path)

ImportError: No module named robots