function doSection ($attrstr) {
	$attrstr = html_entity_decode($attrstr);
	$attr = new Attributes($attrstr);
	$preface = $attr->getAttrib('preface');
	if ($preface !== false) {
/*		flush_section(0);
		if ($preface == 'start')
			$ret = "<abstract>";
		elseif ($preface == 'end')
			$ret = "</abstract>"; */
	}
	else {
		global $current_section;
		$level = $attr->getAttrib('level');
		$ret = flush_section($level) . "<section";
		$current_section = $level;
		$label = trim($attr->getAttrib('label'));
		if ($label != '') {
			$ret .= ' id="'.substitute_umlauts($label).'"';
			$ret .= ' wikipage="'.substitute_umlauts($label).'"';
		}
		$title = $attr->getAttrib('title');
		$ret.= "><title>".xmlencode($attr->getAttrib('title'))."</title>";
	}
	return $ret;
}