setting up apache behind a forward proxy

I have an Internet connection which is behind a forward proxy开发者_C百科.I have to use the proxy server ip address & port No. to connect to the internet.I have installed apache web server in my machine.The apache is configured to use ProxyPass (meaning - it has to fetch documents from an external site).But the forward proxy blocks any such request.How do I set up apache to use the forward proxy server's ip address & port No to access external urls.

If you wanted to proxy say a site from your machine through the corporate proxy, like I recently had to do for a Centos installation, you would use this in your apache config:

ProxyPass       /centos1/  http://ftp.riken.jp/

ProxyPassReverse /centos1/ http://ftp.riken.jp/

ProxyRemote http://ftp.riken.jp/ http://{corporate proxy here}:{corporate proxy port}