var btnOff  = new Array();
var btnOver = new Array();

for(i=0;i<8;i++){
  btnOff[i]  = new Image();
  btnOver[i] = new Image();
  btnOff[i].src = "../img/common/nl/btn_"+i+"_off.gif";
  btnOver[i].src= "../img/common/nl/btn_"+i+"_over.gif";
}

function btn_over(i){
 if (i != current_menu) document["btn_"+i].src=btnOver[i].src;
}

function btn_out(i){
 if (i != current_menu) document["btn_"+i].src=btnOff[i].src;
}