$(document).ready(function() {
  $('form').submit(function() {
    if(typeof jQuery.data(this,"disabledOnSubmit") == 'undefined') {
      jQuery.data(this,"disabledOnSubmit",{ submited: true });
      $('input[type=submit],input[type=button]',this).each(function() {
        $(this).attr("disabled","disabled");
      });
      return true;
    }
    else
    {
      return false;
    }
  });
});