if(navigator.appVersion.charAt(0) >= "3"){
  img = new Array();
  img[0] = new Image; img[0].src = "../images/head_11.gif";
  img[1] = new Image; img[1].src = "../images/head_11_on.gif";
  img[2] = new Image; img[2].src = "../images/head_13.gif";
  img[3] = new Image; img[3].src = "../images/head_13_on.gif";
  img[4] = new Image; img[4].src = "../images/head_15.gif";
  img[5] = new Image; img[5].src = "../images/head_15_on.gif";
  img[6] = new Image; img[6].src = "../images/head_17.gif";
  img[7] = new Image; img[7].src = "../images/head_17_on.gif";
  img[8] = new Image; img[8].src = "../images/head_19.gif";
  img[9] = new Image; img[9].src = "../images/head_19_on.gif";
  img[10] = new Image; img[10].src = "../images/head_21.gif";
  img[11] = new Image; img[11].src = "../images/head_21_on.gif";

}
function chg_img(a,b){
  if(navigator.appVersion.charAt(0) >= "3"){
  document.images[a].src=img[b].src;
  }
}

<!--
//--------------  comment popup window  --------------
function openWin(theURL,winName) { 
newwin = window.open(theURL,winName,"height=600,width=430,status=no,scrollbars=yes,resizable=no");
newwin.focus();
}
//-->