function wechsel(evt)
	{
         if(document.images)
         	{
                 evt = (evt) ? evt: ((window.event) ? window.event : null);
                 if(evt)
                 	{
                         var elem = (evt.target)? evt.target: ((evt.srcElement)? evt.srcElement : null);
                         if(elem && elem.className =="na")
                         	{
                                 switch(evt.type)
                                 	{
                                         case "mouseover":
					 elem.src='../nav/'+elem.id+'x.gif';
                                         break;
                                         case "mouseout":
					 elem.src='../nav/'+elem.id+'.gif';
                                         break;
                                         }
                                 }
                         if(elem && elem.className =="na1")
                         	{
                                 switch(evt.type)
                                 	{
                                         case "mouseover":
					 elem.src='../../nav/'+elem.id+'x.gif';
                                         break;
                                         case "mouseout":
					 elem.src='../../nav/'+elem.id+'.gif';
                                         break;
                                         }
                                 }
                         }
                 }
         }

document.onmouseover=wechsel;
document.onmouseout=wechsel;