#!/usr/bin/perl -w

use strict;

my $d = "[0-9A-Fa-f]";
my $dd = "$d$d";

while (<DATA>) {
        /($dd([:-])$dd(\2$dd){4})/o && print $1, "\n"
}

__END__
My MAC address is 00-00-00-00-00-00 over there,
and it's 00:00:00:00:00:00 over here, and
the date/time happens to be 2001-05-25-15:27.
Note that 00:00-00:00-00:00 isn't really valid.
Oh, and I have one address of DE:AD:BE:EF:21:12.