function addLoadEvent(func){
        var oldonload = window.onload;
        
        if(typeof window.onload != 'function'){
            window.onload = func;
            
        }else{
            window.onload = function(){
                oldonload();
                func();
            }
        }
    }
    /* main tab */
    function main_tab(){
     if(!document.getElementById("main_tab01_Img")) return false;
     if(!document.getElementById("main_tab02_Img")) return false;
     if(!document.getElementById("main_tab01")) return false;
     if(!document.getElementById("main_tab02")) return false;

     var target1 = document.getElementById("main_tab01_Img");
     var target2 = document.getElementById("main_tab02_Img");
     var source1 = document.getElementById("main_tab01");
     var source2 = document.getElementById("main_tab02");
     var main_tab_more = document.getElementById("main_tab_more");

     target1.onmouseover = function(){
      target1.src = "/image/main/tab_01r.gif";
      target2.src = "/image/main/tab_02.gif";
      
	 main_tab_more.innerHTML='<a href="/media/press.html"><img  src="/image/main/tab_more.gif" /></a>';

      source1.style.display = "block";
      source2.style.display = "none";
     }

     target2.onmouseover = function(){
      target1.src = "/image/main/tab_01.gif";
      target2.src = "/image/main/tab_02r.gif";
	 main_tab_more.innerHTML='<a href="/media/event.html"><img  src="/image/main/tab_more.gif" /></a>';
	  
      source1.style.display = "none";
      source2.style.display = "block";
     }

    }

    addLoadEvent(main_tab);