[chicks]$ perl x
-33:-7:-47:-19
33:7:47:19
[chicks]$ cat x
#!/usr/bin/perl -w 

use Date::Calc qw/Delta_DHMS/;


my @date_one = qw/2002 04 25 23 12 40/;
my @date_two = qw/2002 03 23 15 25 21/;

my ($dd, $dh, $dm, $ds) = Delta_DHMS(@date_one, @date_two);
print "$dd:$dh:$dm:$ds\n";

($dd, $dh, $dm, $ds) = Delta_DHMS(@date_two, @date_one);
print "$dd:$dh:$dm:$ds\n";