There are many ways to do it but here is a pretty simple and self explanatory one: 
use strict;
use warnings;
use Date::Calc qw(check_date);

my $date = "9999/12/11";
my($year,$month,$day) = $date =~ /(\d+)\/(\d+)\/(\d+)/;
print "$year/$month/$day is ";
if(check_date($year,$month,$day) && $year >=1753 && $year <= 9999)
{
    print "valid";
}
else
{
    print "not valid\n";
}

[download]
I don't think you are going to be able to do a complete validation using just a regex.

Chris

In reply to Re: regular expression help by ChrisR
in thread regular expression help by Anonymous Monk

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