Bug report #35958 must have the most obscure one ever:

"strftime usually returns a string from the number of seconds since 1 jan 1970. Now, it lags and returns a string representing 23 seconds too late."

If you know what's going on though, it isn't really that weird.

He talks about the leap seconds that have been added to keep things straight, and how that's affecting PHP's built-in date/time functionality. He also shows an example of how you can get the "more correct" time versus the normal output...]]> Wed, 11 Jan 2006 06:41:13 -0600