[mod_python] Cant make test work

Installed mod_python 3.2.10 into this environment
	OS CentOS 4 (default in the Rocks 4.1 distribution)
	Apache 2.0.52
	Python 2.3

Followed the install instructions to the letter.
However the test does not work for me. I.e., pointing my browser at
http://localhost/mptest/mptest.py
just returns the listing of mptest.py, but not the results of running
it against the python interpreter.

/etc/httpd/conf/httpd.conf does contain the line
LoadModule python_module modules/mod_python.so


and /usr/lib/httpd/modules/mod_python.so exists.

/var/www/html/mptest/.htaccess does contain
AddHandler python_module .py
PythonHandler mptest 
PythonDebug On 

and mptest.py contains

from mod_python import apache
def handler(req):
   req.content_type = 'text/plain'
   req.write("Hello World!")
   return apache.OK

I'm stuck

Ronald