[mod_python] mod_python not working.

OK< I have successfully compiled the mod_python module (v. 3.0.3) on
Solaris, installed, and have configured Apache (v. 2.0.45) according to
the 2.4 Testing section in the docs:

    LoadModule python_module  modules/mod_python.so

    <Directory /some/directory/htdocs/test>
      AllowOverride   FileInfo
      AddHandler      python-program .py
      PythonHandler   mptest 
      PythonDebug     On 
    </Directory>

I have created my mptest.py file:

from mod_python import apache

    def handler(req):
        req.send_http_header()
        req.write("Hello World!")
        return apache.OK

Restart Apache and I get a 500 Internal Server Error and 
 "make_obcallback: could not import mod_python.apache." in my error log.
Any ideas?