String.prototype.trim = function() {
  return this.replace(/^\s+|\s+$/g, "");
}

function flagCheckboxes(element) {
  var elementForm = element.form;
  var i = 0;

  for (i = 0; i < elementForm.length; i++) {
    if (elementForm[i].type == 'checkbox') {
      elementForm[i].checked = element.checked;
    }
  }
}