function checkBrowser(){
  this.ver=navigator.appVersion
  this.dom=document.getElementById?1:0
  this.ie5=(this.ver.indexOf("MSIE 5")>-1 && this.dom)?1:0;
  this.ie4=(document.all && !this.dom)?1:0;
  this.ns5=(this.dom && parseInt(this.ver) >= 5) ?1:0;
  this.ns4=(document.layers && !this.dom)?1:0;
  this.bw=(this.ie5 || this.ie4 || this.ns4 || this.ns5)
  return this
}

bw=new checkBrowser();

function replace(obj){
  return bw.dom ? document.getElementById(obj) : document.all[obj];
}
function search(obj){
  return bw.dom ? parent.document.getElementById(obj) : parent.document.all[obj];
}