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") == "external")
     anchor.target = "_blank";
 }
}

function PopupPic(sPicURL) {
 window.open( "bigImage.html?"+sPicURL, "",  
 "width=300,height=400,resizable=no,directories=no,location=no,menubar=no,scrollbars=no,status=no");
}

window.onload = externalLinks;