We would like to do proxy pass to alias a URL 1 with URL 2 (with a virtual directory) but using the same content for URL 1

Cool, yes the two URLs have their own ip virtual addresses have their own virtual servers and own pools. We would just like to do this for SEO purposes. To have a simple example, let's say we have msn.com and espn.com with their own ip addresses, own virtual servers, and own pools. We would like for msn.com to be changed in the URL of the browser to espn.com\msn but still contain the msn.com web content. What's the best way do this?

Thanks