Just as it appears the world's computers have smitten the Y2K bug, officials say there could be another date problem on February 29th.
That's because of a little-known calendar rule that determines whether a year is a leap year or not.
Normally, leap years are every four years except for years ending in double-zero.
Many computers may assume that's the case this year -- and incorrectly skip February 29th.
But if a year is evenly divisible by 400, another rule comes into effect that again makes it a leap year.
It's an exception to an exception that only comes into play every 400 years.