[mod_python] Setting PythonOption to an empty string.

I might be missing something, but I want to be able to set a 
PythonOption variable
to be an empty string. Alternatively, is there a way in the .htaccess 
file to unset
a PythonOption variable which has been inherited from a parent 
directory?

When I try and set the variable to an empty string. Ie.,

   PythonOption Name ""

I get an Apache error:

> Internal Server Error
>
> The server encountered an internal error or misconfiguration and was 
> unable to complete your request.
>
> Please contact the server administrator,  you at example.com and inform 
> them of the time the error occurred, and anything you might have done 
> that may have caused the error.
>
> More information about this error may be available in the server error 
> log.
> Apache/2.0.51 (Unix) mod_python/3.1.3 Python/2.3 Server at localhost 
> Port 8080

This is a little bit annoying. :-(

--
Graham Dumpleton (grahamd at dscpl.com.au)