How to rewrite WordPress permalinks for reverse proxy?

[ufmedia]

Our main site, www.domain.com, is on an IIS 6 server.  When we started our blog, we wanted to put it in a subdirectory (domain.com/blog), but we couldn't because our IT people refused to support it.  Instead, we built it on a third-party Apache server and configured it to open under blog.domain.com.  However, I came across this SEOmoz post about the glories of reverse proxies, so I've persuaded our IT people to take a swing at it.

We got it to work on a staging server, but the permalinks won't change (still appear as blog.domain.com/slug).  The IT guys say it's due to a configuration problem with WordPress.  Can somebody out there point me in the right direction as far as working out the URL issues with this?

[EricaMcGillivray]

Have you gone in and changed the admin panel information about your site?