function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      oldonload();
      func();
    }
  }
}


function prepareGallery() {
if (!document.getElementsByTagName) return false;
if (!document.getElementById) return false;
if (!document.getElementById("imagegallery")) return false;
var gallery = document.getElementById("imagegallery");
var links = gallery.getElementsByTagName("a");
for ( var i=0; i < links.length; i++) {
links[i].onclick = function() {
return showPic(this);
}
links[i].onkeypress = links[i].onclick;
}
}

function showPic(whichpic) {
var details = document.getElementById("details");
details.innerHTML = '<img id="placeholder" src="" alt="" /><p id="caption">text</p>';
if (!document.getElementById("placeholder")) return true;
var source = whichpic.getAttribute("href");
var placeholder = document.getElementById("placeholder");
placeholder.setAttribute("src",source);
if (!document.getElementById("caption")) return false;
if (whichpic.getAttribute("title")) {
var text = whichpic.getAttribute("title");
} else {
var text = "";
}
var caption = document.getElementById("caption");
if (caption.firstChild.nodeType == 3) {
caption.firstChild.nodeValue = text;
}
return false;
}

addLoadEvent(prepareGallery);