We received an email today from one of our readers (Scott) with the following information:

"It might be worth mentioning that Microsoft has ended support for Windows Server 2003 RTM/"Gold" (no Service Pack). The new patches applicable to Windows 2003 (MS07-027, -028, -029) will only install on 2003 SP1 or later. So if any readers haven't fully deployed SP1 or SP2 yet, now would certainly be a good time to do so. If that's not possible, patches might be available from Microsoft (for a fee) under the Extended Support program."

I checked with Microsoft for confirmation on this and received this information back:

The dates for W2K3 SP0 (RTM/Gold), SP1, SP2

Product Name	Service Pack	Gen. Avail. Date	Support Retired
Windows Server 2003	Service Pack 0 (RTM)	May 28th 2003	April 10th 2007
Windows Server 2003	Service Pack 1	March 30th 2005	April 14th 2009
Windows Server 2003	Service Pack 2	March 13th 2007	Not Applicable

For SP2:
See Note Support ends either 12 or 24 months after the next service pack releases or at the end of the product's support lifecycle, whichever comes first. Visit the Lifecycle page to find the support timelines for your particular product.

Microsoft has some information about the Main LifeCycle at:
support.microsoft.com/lifecycle/Default.aspx

And the page with the various dates is here:
support.microsoft.com/gp/lifesupsps#Windows

Thanks to Scott for calling this to our attention and to Microsoft for getting back to us with the information.