Reverse Proxy, permalinks and 'Redirection' plugin

Hi All

Our current server configuration is we have one server managing the reverse proxy, which forwards the request to another server with the hosted wordpress.
http://www.foo.com/ -> http://bar.private.lan/wordpress/

I’ve slowly been working out all of the bugs so far. In the wp-config, i have rewritten a few things:

Manually defining WP_SITEURL and WP_HOME to: http://www.foo.com/
To prevent odd dynamic behaviour.

And rewriting the URI
$_SERVER[‘REQUEST_URI’] = str_replace(“wordpress/”, “”, $_SERVER[‘REQUEST_URI’]
To prevent more odd dynamic behaviour in the admin pages.

However, I am now attempting to setup permalinks, and I’m not getting very far. Only the default option works, and all options will display the post on the landing page. However clicking the link will cause a an error 404. The log file (on bar.private.lan) reads:
[client 192.168.1.1] File does not exist: /dir/webroot/wordpress/2011, referer: http://www.foo.com/

Symbolic linking doesn’t appear to be the issue, i’ve had nothing but problems using a virtual host setup on the host machine, and although this topic suggested a plugin, I’ve also had nothing but pain getting that to work.

Is there something I am missing? Or perhaps someone could provide a more thorough guide to using the ‘Redirection’ plugin?

Much appreciated

Kris Robson