public function buildReminders($starttime, $endtime) {
		if (!$this->hasReminders()) {
			return true;
		}
		
		$starttime = sanitize_int($starttime);
		$endtime = sanitize_int($endtime);
		
		// first delete any existing reminders for this time period
		$this->removeReminders($starttime, $endtime);
		
		$reminders = elgg_get_metadata(array(
			'guid' => $this->guid,
			'metadata_name' => 'reminder',
			'limit' => false
		));
				
		// create reminders in this time period
		$starttimes = $this->getStartTimes($starttime, $endtime);
		foreach ($starttimes as $s) {
			foreach ($reminders as $r) {
				$reminder = $s - $r->value;
				if ($reminder < time()) {
					continue; // already passed
				}
				
				$this->annotate('reminder', $s - $r->value, ACCESS_PUBLIC);
			}
		}
		return true;
	}