Echo returns blank page in default theme

Hi,

I was trying to enable echo with HTML mail, but I kept getting blank pages in my email. Therefore, I went and tried to create a custom page, only to use the function echo_themed_page. But even this kept me giving back blank pages. Whatever I changed the theme for. What could be wrong?

function _custom_menu() {
  $items = array();
  $items['_custom/test'] = array(
    'page callback' => '_custom_test',
    'type' => MENU_NORMAL_ITEM,
    "access callback" => array("_custom_allow"),
  );
  return $items;
}
function _custom_test() {
  echo "aap";
  echo echo_themed_page("test", "haha", "golfers");
  exit;
}
function _custom_allow() { return true; }