lastSibling:function(node){
var tempObj = node.parentNode.lastChild;
while(tempObj.nodeType!=1 && tempObj.previousSibling!=null)
{
tempObj=tempObj.previousSibling;
}
return (tempObj.nodeType==1)?tempObj:false;
}

'last-child': function(){
var element = this;
while ((element = element.nextSibling)){
if (element.nodeType == 1) return false;
}
return true;
}