Trouble with Menu / Navigation and Aliaspath

//SimpleMenu 0.1
//Luca Allulli December 2005
//License: GNU General Public License 2

//Begin param
$rootid=isset($rootid)? $rootid: 0;
$pageid=isset($pageid)? $pageid: $modx->documentIdentifier;
//End param

$output="";

$children=$modx->getDocumentChildren($pageid);
if(!empty($children)) {
	foreach($children as $child) {
		if($child['id']!=$pageid)
			$item='<li> <a href="[~'.$child['id'].'~]">'.$child['pagetitle']."</a></li>\n";
		else
			$item="<li>".$child['pagetitle']."</li>\n";
		$output.=$item;	
	}	
	$output="<ul>\n".$output."</ul>\n";	
}

$pid=$pageid;

if($pid==rootid)
	$goon=false;
else {
	$goon=true;
	$ris=($modx->getParent($pid));
	$oldid=$pid;
	$pid=$ris['id'];
}

while($goon) {
	$children=$modx->getDocumentChildren($pid);
	$before=true;
	$out1="";
	$out2="";
	foreach($children as $child) {
		if($child['id']!=$pageid)
			$item='<li> <a href="[~'.$child['id'].'~]">'.$child['pagetitle']."</a></li>\n";
		else
			$item="<li>".$child['pagetitle']."</li>\n";
		if($before)
			$out1.=$item;
		else
			$out2.=$item;
		if($child['id']==$oldid)
			$before=false;
	}
	$output="<ul>\n".$out1.$output.$out2."</ul>\n";
	$oldid=$pid;
	if($pid==$rootid)
		$goon=false;
	else {
		$ris=($modx->getParent($pid));
		$pid=$ris['id'];
	}
}
return $output;