function validForm(obj)
{
  var radioChecked = true;
  var checkboxChecked = true;
for (var i=0; i<obj.elements.length;i++)
 {
    var currentElement = obj.elements[i];
    var currentType = currentElement.type;
    if (currentType == 'text')
    {
    if(null!=obj.elements[i].getAttribute("required")){  
	    if (!obj.elements[i].value)
	      {
	        alert('You must fill in all the required fields!');
	        currentElement.focus();
	        return false;
	      }
	    }
    }
    if (currentType == 'checkbox' && currentElement.checked)
    {
      checkboxChecked = true;
    }
    if (currentType == 'checkbox' && !currentElement.checked && null!=obj.elements[i].getAttribute("required"))
    {
		alert('You have empty checkboxes!');      
    	return false;
    }
  }

  if (!checkboxChecked)
  {
    alert('You have empty checkboxes!');
    return false;
  }
  return true;
}