function setExternalLinks() {
 if (!document.getElementsByTagName) {
 return null;
 }
 var anchors = document.getElementsByTagName("a");
 for (var i=0;i < anchors.length;i++) {
 var anchor = anchors[i];
 if (anchor.getAttribute("href") && anchor.getAttribute("rel") == "target_blank") {
 anchor.setAttribute("target", "blank");
 }
 }
 }
 window.onload = setExternalLinks;