Yesterday when TechRepublic’s Twitter account put the call out asking if anyone had seen any leap year bugs, I did not expect Microsoft to reply in the affirmative.

An update on the Windows Azure blog tells the grim tale. On Feb 28, 5:45pm Pacific Standard Time, Azure operations tracked down a software bug to time calculations that were incorrect due to the leap year.

Nine hours later, service was resumed to most of Azure’s customers, but some were still experiencing issues at the time of writing.

Microsoft has said that it will provide a root cause analysis at the end of this incident.

It’s a reminder that even the mightiest can fall foul of bugs that really should have been sorted out years ago, and one expects better from a company the size of Microsoft.

Closer to home, and the NAB-owned Health Industry Claims and Payments Service had a problem with the entire existence of February 29. “Someone forgot to add the 29th of February,” a source told the Sydney Morning Herald.

If you suffered the same fate yesterday, take solace in the fact that you are not alone, and a system as big as Azure can fall over as well.