Web Hosting/IP Translation/DSL Connectio

I am host my company’s website on a machine inside my company’s LAN. Our new DSL ISP has provided us with an IP address for the nodes on the Internet to see us, but when I try to browse to it,using the ISP given IP, from inside our LAN the client appears to find the site but will not receive the information from the server. When I browse to it from outside our LAN it works just fine.