function externalLinks() { 
	if (!document.getElementsByTagName) return; 
	var anchors = document.getElementsByTagName("a"); 
	for (var i=0; i<anchors.length; i++) { 
		var anchor = anchors[i]; 
		if (anchor.getAttribute("href") && anchor.getAttribute("rel")) 
			if (isExternal(anchor.getAttribute("rel")))
				anchor.target = "_blank"; 
	} 
} 
window.onload = externalLinks;

function isExternal(rel) {
	var temp = new Array();
	temp = rel.split(' ');
	for (i=0; i < temp.length; i++) {
		if (temp[i].toLowerCase()=="external")
			return true;
	}
}