var _POPUP_FEATURES = 'location=0,statusbar=0,menubar=0,width=400,height=300';

function methodOf(thisObj) {
	if (!Function.apply) {  // JScript older than 5.5
		var thisObjClass = '[object Window]';
	}
	else 
		var thisObjClass = Object.prototype.toString.apply(thisObj);
	
	if (thisObjClass != '[object GlobalObject]' && thisObjClass != '[object Global]' && thisObjClass != '[object Window]') 
		return true;
	else 
		return false;
}

function isUndefined(a) {
	if (methodOf(this)) 
		a = this;
	return typeof a == 'undefined'
}
 
function raw_popup(url, target, features) {
  if (isUndefined(features)) {
    features = _POPUP_FEATURES;
  }
  if (isUndefined(target)) {
    target = '_blank';
  }
  var theWindow =
    window.open(url, target, features);
  theWindow.focus();
  return theWindow;
}

function link_popup(src, features) {
  return raw_popup(src.getAttribute('href'), src.getAttribute('target') || '_blank', features);
}