var oiBuf=null;
var oiCap=false;
var oiInitDone = false;


function joi_init(){
  var browserName=navigator.appName;
  var browserVersion=parseInt(navigator.appVersion);

  oiCap= 
    (browserName.indexOf("Netscape")>=0 && browserVersion>=3) ||
    (browserName.indexOf("Internet Explorer")>=0 && browserVersion>=4);
    oiInitDone=true;
}
function joi_isCapability(){
  if (!oiInitDone) joi_init();
  return oiCap;  
}
function joi_register(id,normalSrc,overSrc,downSrc){
  if (!oiInitDone) joi_init();

  if (oiCap)
  {
    if (overSrc==null)   overSrc=normalSrc;
    if (downSrc==null)   downSrc=overSrc;

    oiBuf=new Array(id,true,new Image(),new Image(),new Image());
    oiBuf[2].src=normalSrc;
    oiBuf[3].src=overSrc;
    oiBuf[4].src=downSrc;
    eval("oiObj"+id+"=oiBuf;");
  }
}
function joi_setNormal(id,msg){
  if (oiCap)
  {
    var regObj=eval("oiObj"+id);
    if (regObj[1])
      document[id].src=regObj[2].src;
  }
	if (msg!='') window.status=msg;
}
function joi_setLoadImgToId(id,idChange){
  if (oiCap)
  {
    var regObj=eval("oiObj"+id);
    if (regObj[1] && document[idChange])
      document[idChange].src=regObj[2].src;
  }
}
function joi_setOver(id,msg){
	if (msg!='') window.status=msg;
  if (oiCap)
  {
    var regObj=eval("oiObj"+id);
    if (regObj[1])
      document[id].src=regObj[3].src;
  }
  return true;
}
function joi_setDown(id){
  if (oiCap)
  {
    var regObj=eval("oiObj"+id);
    if (regObj[1])
      document[id].src=regObj[4].src;
  }
}
function joi_lock(id){
  if (oiCap)
    eval("oiObj"+id)[1]=false;
}
function joi_unlock(id){
  if (oiCap)
    eval("oiObj"+id)[1]=true;
}