[mod_python] Cookies & mod_rewrite

Hi

I'm using mod_python to perform NTLM authentication. In my handler script
"ntlmhandler.py" a cookie gets set using the following code:

cookie = Cookie.Cookie('username', user, path='/')
Cookie.add_cookie(req, cookie)   

With the following apache conf for some reason the cookie is not getting
passed in the request to the rewrite url. When requesting a page in the
/ntlm directory without the rewrite rule in place, the above cookie is
getting set fine. Does anybody have any ideas why this might be the case?

<VirtualHost 192.168.100.100:80>
    ServerName myserver.com
    KeepAlive On

    DocumentRoot /ntlm/

    <Directory /ntlm> 
        AddHandler mod_python .py
        PythonAuthenHandler ntlmhandler
        PythonDebug On
        AuthType NTLM
        require valid-user

        RewriteEngine On
        RewriteRule ^(.*)$
http://192.168.100.100:5090/VirtualHostBase/http/myserver.com:80/dev/content
_root/VirtualHostRoot/$1 [P,L]    

    </Directory>    

</VirtualHost>

Regards

Guy

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