When Microsoft finally ships the long-awaited 64-bit editions of its latest server and client operating systems next month, it will be just the tip of a 64bit iceberg.

The software giant plans to offer 64bit versions of several of its applications this year and next, including SQL Server, Exchange, Commerce Server, Microsoft Operations Manager and Virtual Server. Today, SQL Server 2000 is the only Microsoft application offered on a 64bit platform.

Microsoft has been briefing partners and developers during its Route64 Training Tour on its future plans for its applications on AMD64 and Intel's EM64T processors, so-called X64 platforms.

According to slides presented to developers in February, Microsoft has at least 12 products slated for 64bit versions over the next 21 months.

"The information in the slides is incomplete and is in the process of being updated, and we will have more to share at the end of April," a Microsoft spokesperson cautioned.

Nevertheless, the slides show that first out of the gate will be SQL Server 2005 and Visual Studio 2005, which will both have X64 and Itanium support.

In the third quarter of the year, Microsoft is scheduled to ship Commerce Server, BizTalk Server and Host Integration Server 2005, all on the X64 platform only.

Sometime in the second half of the year, Microsoft is set to release an X64 version of Virtual Server 2005 with Service Pack 1 of that software, and for Virtual PC 2004 with SP2. Also later this year, Microsoft plans to release an X64 and Itanium version of Services for Unix, an integration and migration platform.

Next year, Microsoft is scheduled to release a version of Microsoft Operations Manager for both X64 and Itanium. 2006 will include X64 releases of Exchange 12, Virtual PC Server Version 2 and Virtual Server 2.0.

Microsoft already has support for Intel's Itanium 64-bit processor on the Enterprise and Datacenter versions of Win 2003 and SQL Server 2000, but the advent of 32bit processors with 64-bit extensions from both AMD and Intel is finally motivating Microsoft to play catch-up with Unix and Linux platforms that have had 64bit support for years.

"Microsoft has been waiting for 64bit to become a high-volume hardware platform before making a commitment," says Dan Kusnetzky, program director for operating environments and serverware at research firm IDC. "With 64bit applications, they can better compete in the market for systems for high-performance and computational applications. Right now, when you talk about supercomputing, you seldom hear anyone talk about Windows."

He says the new X64 processors mean that users can look at migration as evolutionary and not disruptive. "If users had to move everything all at once, top to bottom, they would resist a change like that," he says.