Build numbers vs release dates for MS Exchange

If you are an exchange admin, it's important  to keep on top of your versions across the organization. Do you ever need to take a step back and ask: "Which service pack am I running on  such and such a server?"? I have been there, and that's why I found this list of releases and build numbers for exchange very useful.

To find out the build number, open Exchange System Manager, and click "About Exchange System..." under "Help".  As you can see below, I have build number 6.5.7226 on this particular server, which corresponds to Exchange 2003 SP1. Which is annoying for me because it means I'm going to have to spend the afternoon installing Exchange 2003 SP2 before I can set up Intelligent Message Filtering. Well, at least I know... and now you do too!!! :)