Looks like this example doesn't work: Leap Seconds and Date Math
The presence of leap seconds can cause some strange anomalies in date math. For example, the following is a legal datetime: my $dt = DateTime->new( year => 1971, month => 12, day => 31, hour => 23, minute => 59, second => 60, time_zone => "UTC" ); It returns undef with DateTime 0.2901 and prints a warning: Invalid second value (60) -- Mike Mike Schilli [EMAIL PROTECTED]