#!/usr/bin/perl -w
use strict;
use Data::Dumper;

my %hash;
my $currentkey;
my $inkey = 0;

while (<DATA>) {
  chomp;

  next if /^\s*$/; # skip blank lines

  if ($inkey == 0) {
    $currentkey = $_;
    $inkey = 1;
    next;
  }

  if (/^\*+END\*+$/) {
    $inkey = 0;
    next;
  }

  push @{$hash{$currentkey}}, $_;
}

print Dumper(%hash), $/;

__DATA__
mykeyword1
foo1
bar1
***END***
mykeyword2
***END***
mykeyword3
baz3
foo3
bar3
***END***
mykeyword4
baz4
***END***

##</code><code>##

$VAR1 = 'mykeyword3';
$VAR2 = [
          'baz3',
          'foo3',
          'bar3'
        ];
$VAR3 = 'mykeyword1';
$VAR4 = [
          'foo1',
          'bar1'
        ];
$VAR5 = 'mykeyword4';
$VAR6 = [
          'baz4'
        ];