Viewing the decoded string in the debugger, it appears that all the data is there...

The first 8 bytes are probably the two dates, perhaps packed seconds since epoch. unpack those and convert them to dates with localtime. The remaining data is null-separated; split /\0/ to get the remaining fields. The last one does appear to be an MD5 hash, as you said.

Update: How about a code example? :) 

#!/usr/local/bin/perl -w

use strict;
use CGI qw/:standard/;
use CGI::Carp qw(fatalsToBrowser);
use MIME::Base64;
use CGI::Cookie;

my $query = new CGI;
my %cookies = fetch CGI::Cookie;
my $cookie = $cookies{'Cookie-Name'}->value;

print $query->header;
print $query->start_html;
print "<h1>Cookie</h1><br>\n";
print "Straight cookie: $cookie\n<br><br>\n";

my $decoded = decode_base64($cookie);

my($time1, $time2) = unpack 'NN', $decoded;

substr($decoded, 0, 8) = '';

print join "<BR>", "Decoded cookie:",
  scalar(localtime $time1), scalar(localtime $time2),
  split /\0/, $decoded;

print $query->end_html;

[download]

In reply to Re: Base64 Encoded cookie is giving me headaches! by chipmunk
in thread Base64 Encoded cookie is giving me headaches! by tame1

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