I wouldn't use regex to split/read the timestamp. I would use one of the date handling modules (I like DateTime or Time::Piece) and then perform the date arithmetic with the module. Then spit out the modified timestamp in the format that you want. Something like this with DateTime: 
use DateTime;
use DateTime::Format::Strptime;

my $strp = DateTime::Format::Strptime->new(
  pattern => '%a, %d %Y %H:%M:%S %z'
);
my $dt = $strp->parse_datetime('Sat, 20 Feb 2010 01:31:52 GMT');
$dt->add(days => 1);

$dt->set_formatter('%a, %d %Y %H:%M:%S %z');
my $date_string = "$dt";

[download]
 Sorry: didn't see the 'cant install other modules' on my scan

In reply to Re: Modifying cookie expire date by mpeters
in thread Modifying cookie expire date by mellin

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