First: Change your -domain line to:

     -domain => '.blahblah.com'
You need at least two periods in the domain line (to make sure you don't try to set a domain-wide cookie across a top level domain like .com or something).

Second: I prefer to use CGI::Cookie. I've never had a problem with it.

SET COOKIE

use CGI::Cookie;
my $c = new CGI::Cookie(
  -name    =>  'COOKIENAME',
  -value   =>  'Whosyerdaddy',
  -expires =>  '+1M',
  -domain  =>  '.domain.com'
);
print "Set-Cookie: $c\n";
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READ COOKIES

my %temp = parse CGI::Cookie($ENV{HTTP_COOKIE});
my %cookies;
foreach (keys %temp) {
    $cookies{$_} = shift @{$temp{$_}{value}};
}
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I'm not sure why parse returns an array of values for each cookie, but it does. Yes, I could have used map, but I haven't had my coffee yet this morning. :)

TOSS YOUR COOKIES

print header();
my $debug = 1;
# READ COOKIE CODE
if ($debug) {
  foreach (keys %cookies) {
    print "$_: $cookies{$_}<BR>\n";
  }
}
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Redirect to a simple little script that runs this code. That should tell you how well your cookies worked.