window.onload = function() {
  addRelFunction();
  };

/*
function addRelFunction() {
   var allLinks = document.getElementsByTagName("a");
     for (var i=0; i<allLinks.length; i++) {
       var title_text = allLinks[i].getAttribute("class");
       if (title_text == "gs_image_link") {
         allLinks[i].rel = 'lightbox';
         // allLinks[i].setAttribute("rel", "lightbox");
         // alert(allLinks[i].getAttribute("rel"));
         };
    };
};
*/

function addRelFunction() {
   var allLinks = document.getElementsByTagName("a");
     for (var i=0; i<allLinks.length; i++) {
       var title_text = allLinks[i].className;
       if (title_text == "gs_image_link") {
         allLinks[i].rel = 'lightbox';
         // allLinks[i].setAttribute("rel", "lightbox");
         // alert(allLinks[i].getAttribute("rel"));
         };
    };
};