function getObject(obj) {
  if (document.all) {
      return document.all(obj);
  }
  if(document.getElementById) {
      return document.getElementById(obj);
  }
  return null;
}
function count(input,output,message,numChars) {
  var inputObj=getObject(input);
  var outputObj=getObject(output);
  var length=numChars - inputObj.value.length;
  if(length <= 0) {
    length=0;
    inputObj.value=inputObj.value.substr(0,numChars);
  }
  outputObj.innerHTML = message.replace("{CHAR}",length);
}