How to rewrite some code from 1.9 to beta11

How to rewrite some code from 1.9 to beta11
It is for http://drupal.org/project/privatemsg (privatemsg-5.x-2.x-dev.tar.gz)

function pm_subscriptions_subscriptions_handle($message, $cron = FALSE) {
  if (!$cron) {
    subscriptions_hold($message, 'pmsg', 'insert', $message->uid);
  }
  $variables = ($unserialized = unserialize($message->variables)) ? $unserialized : array();
  pm_subscriptions_mail_edit_variables($variables);
  subscriptions_mailvars($message->type, $message->id, $message->author, 'pmsg', $cron);
}