function changeBGon() {
  with (event.srcElement.style) {
    backgroundColor='#DDDFFF';
  }
};

function changeBGoff() {
  with (event.srcElement.style) {
    backgroundColor='';
  }
};

if (document.all) {
  with (document.forms[0]) {
    for (i=0; i<elements.length; i++) {
      switch (elements[i].type) {
        case "text" :
        case "textarea" :
        case "select-one" :
        case "select-multiple" : { elements[i].onfocus = changeBGon; elements[i].onblur = changeBGoff; break };
        default : { break };
      }
    }
  }
}