var click_track = new Array();

function clickedOnce(text_box) {
  if(click_track[text_box] == undefined) {
    setStyle(text_box, 'color', '#000');
    click_track[text_box] = true;
    text_box.value = "";
  }
}
function setStyle(obj,style,value){
  getRef(obj).style[style]= value;
}
function getRef(obj){
  return (typeof obj == "string") ?
  document.getElementById(obj) : obj;
}