Haven't plugged your daylight-saving time bug yet, the one being described as a mini-Y2K? You're not alone, though the deadline's less than a month away.

U.S. daylight-saving time starts March 11, three weeks earlier than usual, in a move authorized by the U.S. Energy Policy Act of 2005. But many software programs don't account for that early shift.

One of the world's largest financial services firms is still getting patches for Linux, Microsoft, and Sun systems and applying them to thousands of servers, says a company executive. The biggest concern is timed events such as overnight batch schedules and trading strategies that could trigger incorrectly, so during the daylight-saving weekend, the company will have a large staff on duty and on call. Another company, White Mountains Re Services, a subsidiary of the White Mountains Re Group reinsurance company, had updated many of its servers, with a handful being finished late last week. Like Y2K, it's thankless work.

But Erik Tomasi, VP of infrastructure, says the company did find some machines that hadn't been updated in a while. Says Tomasi, "Actually, this was a good exercise to make sure all the critical security updates were applied."