active = 'link_0';
function highlightLink(obj){
	if(oldElement = document.getElementById(active)){
		oldElement.className = '';
	}
	active = obj;
	element = document.getElementById(obj);
	element.className = 'current';
}
function highlightNext(){
	var cur = active;
	var pieces = active.split('_');
	var curNum = pieces[1];
	if(curNum != (sp1.getContentPanels().length - 1)){
		highlightLink('link_'+(parseInt(curNum,10) + 1));
	}
}
function hightlightPrev(){
	var cur = active;
	var pieces = active.split('_');
	var curNum = pieces[1];
	if(curNum != 0){
		highlightLink('link_'+(curNum - 1));
	}
}