document.getElementsByClassName = function(str) {
var list = new Array();
var nodes = document.getElementsByTagName('*')
for (i = 0; i<nodes.length; i++){
 if (nodes[i].className.indexOf(str) >= 0){
  list.push(nodes[i]);
}
}
return list;
};

function external_links()
{
	var elements = document.getElementsByClassName('external');
	var elemLength = elements.length;
	for (var i = 0; i < elemLength; i++)
	{
		elements[i].target = "_blank";
	}
}