No IM in Notes Web Client

If I open my mail from my desktop using a browser, I can get into my mail and it attaches to the sametime server so I can use IM. If I use a browser from home, I can get to my mail, calendar, etc. but IM fails to connect to the sametime server. My mail server is in a DMZ. I’m sure I need to open a port on the firewall, but as of yet haven’t been able to find the documentation to achieve it.

Does anyone have a suggestion? If I new the port, I could work with my Internet Services Manager to open the port on the firewall.

Subject: Try opening port 1533 for Sametime (eom)