Rumor has it that Exchange Server 2007 Service Pack 1 will arrive by late October or early November. Fortunately, if you’ve got an Exchange test server running, SP1 is available in a public beta that you can try, and try it you should. Microsoft went to some trouble to make this one worth the download.

[ See also the Test Center Review: Microsoft's marriage of easy communications ]

First, SP1 has a definite smoothing effect on the relationship between Exchange Server 2007 and Office Communications Server 2007. So much so that the unofficial word is that running a combination of OCS and Exchange without SP1 is a mistake. SP1 also addresses a number of administrative concerns that users expressed since Exchange 2007 rolled out, which includes not only updated GUI tools but full Windows Server 2008 and Vista support (‘bout time). Last, it adds to Exchange’s security capabilities by beefing up secure e-mail access, improving support for encrypted e-mails, and introducing an additional high-availability and fail-over option.

That’s the general overview. Specifically, you’ll find end-user goodies in the form of SharePoint and public folder access via the Outlook Web Access (OWA) client -- a feature that might raise some security eyebrows, but Microsoft says it's got that licked. And to keep Web-based messages safer, SP1 now includes support for S/MIME encryption via the OWA client, too. There’s a bunch of new features your end-users will enjoy, including new OWA themes, Office 2007 document converters, and a new monthly scheduling view.

As for the IT admin bennies, most admins will jump for the GUI console and shell updates. On the console side, you’ll now find tools for much of the stuff that was command-line-only in the initial Exchange 2007 release. That includes POP/IMAP management, public folders, VoIP security, and clustering. Exchange’s PowerShell toolkit gains syntax improvements meant to make the whole thing easier to use, as well as specific support for importing and exporting personal folders (PST files) during large mailbox moves. Further, SP1 will support Windows Server 2008 for all Exchange Server roles, and the new OS will benefit from the whole management toolkit.

Another big admin feature is a third flavor of continuous replication. Out of the box, Exchange 2007 came with two ways to keep your message store continuously backed up: An entirely local version that simply drops the replication onto another volume in the same server, and a fully clustered configuration that provided instant fail-over to another server. The new Standby version of continuous replication provides a middle ground, dropping the replicated message store onto another server without requiring clustering. The only caveat is that fail-over will require manual intervention rather than instant automation -- a nice solution for branch offices or SMBs.

There’s yet more to SP1, including an update to ActiveSync and more granular tools such as log management updates and mobile remote wipe confirmation -- but we’re out of space. Bottom line: If you’re running Exchange Server 2007, SP1 isn’t a maybe, it’s a must-have.