Apache Proxy

I've been trying to set up my mod_proxy to redirect all requests from a certain ip address to one page with mod_rewrite, but have been having some trouble.  Any help here?

Thanks, but it doesn't seem to be working.  When I test it, it doesn't redirect.

RewriteEngine on
RewriteCond %{REMOTE_ADDR} ^127\.0\.0\.1$
RewriteRule .* http://www.google.com/ [PT,L]