One problem that has cropped up often for many clients, he said, is that they are still running older operating systems such as Windows NT 4.0, which is not supported by patches from Microsoft Corp. "There's a lot more NT out there than clients thought they had," Cappelli said. "That is a headache certainly." Those users will either have to "hand-hold" their systems through the DST shift or move the operating systems to newer versions. That kind of move brings its own set of risks and challenges.

"Now is not the time to press for a major operating system upgrade," he said.

The DST implementation recommendations from Gartner include the following:

-- After applying patches or manual fixes, conduct tests to verify that the proper times and dates are produced.

-- Review all applications and their interactions with other applications for DST change compliance.