Multiple Domain Hosting

I have just installed a web server running Windows NT 4.0 Server and IIS 4.0. I want to be able to host 4 websites (with 4 domain names) on this server. However, I only have 1 usable public IP address. How could I host these 4 sites in IIS 4.0 using a single IP address? Should I update these MX record of these 4 sites at Network Solutions and point them to a single IP address?