Hi! I guess you will have to work out a way of testing for dates past 2037 and making adjustments. Here are a few snippets that shows you the problem and a work around fix. (Not tested to government standards :-) )

#!/usr/bin/perl
#this shows where you run out of seconds and the 
#signed 32 goes negative. 
$secs_non_leap = 60 * 60 * 24 * 365; # seconds per non-leap year 
$secs_leap = 60 * 60 * 24 * 366;     # seconds per leap year 

$secs =  hex "7FFFFFFF"; # max number a signed 32 can hold 

foreach $year (1970 .. 2040) {
$leap = $year % 4 ? 0 : 1;
$secs -= $leap ? $secs_leap : $secs_non_leap;
print "$year $secs\n";
}
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-----And a fix------------------------------------------------

#!/usr/bin/perl
use warnings;
use strict;
use Date::Manip;

my $far_date = UnixDate(ParseDate("40 years 20 minutes"),"%s");

print "40 years and 20 minutes from now is: ", $far_date,"\n";

print "epoch $far_date seconds translate to: ",
UnixDate(ParseDate("epoch $far_date"),"%m/%d/%Y %H:%M:%S"),"\n";
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