if(navigator.appVersion.charAt(0) >= "3"){
  img = new Array();
  img[0] = new Image; img[0].src = "images/m1_1.gif";
  img[1] = new Image; img[1].src = "images/m1_2.gif";
  img[2] = new Image; img[2].src = "images/m2_1.gif";
  img[3] = new Image; img[3].src = "images/m2_2.gif";
  img[4] = new Image; img[4].src = "images/m3_1.gif";
  img[5] = new Image; img[5].src = "images/m3_2.gif";
  img[6] = new Image; img[6].src = "images/m4_1.gif";
  img[7] = new Image; img[7].src = "images/m4_2.gif";
  img[8] = new Image; img[8].src = "images/m5_1.gif";
  img[9] = new Image; img[9].src = "images/m5_2.gif";
  img[10] = new Image; img[10].src = "images/top_oyo.gif";
  img[11] = new Image; img[11].src = "images/top_oyo2.gif";
}
function chg_img(a,b){  //
  if(navigator.appVersion.charAt(0) >= "3"){
    document.images[a].src=img[b].src;
  }
}