Thirty years ago, programmers figured two digits were enough for the year. No way in heck would the software run long enough for this to be a problem!
The UNIX guys were wrong.
Another operating system used a 32 bit counter to count time in milliseconds from when it's turned on. No way in heck would the system run long enough for this to cause a problem when it rolled over! It rolls over in 49 days. It's in Win 95 and Win 98.
Microsoft was right.
(A tip o' the hat to Norman C. for illuminating this, in comp.risks. See http://support.microsoft.com/support/kb/articles/q216/6/41.asp for the item) -Andy