Need ExchSrvr 4.0 Site Connectors

I’m upgrading Exchange Server 4.0 to 5.5. I’ve set up a separate server to run 5.5, and want to join the site running 4.0, but it can’t unless the 4.0 site is running the Microsoft Exchange Server Connector, which you may recall were not distributed on the CD with the other Exchange code.

If you have this connector or know where I can find it, I’d appreciate it very much.

THanks,
Kevin