swim=function(){
	for(i=0;i<document.images.length;i++)
	if(document.images[i].src.indexOf('bt_')>-1&&document.images[i].src.indexOf('_l.')>-1)
	{	document.images[i].l=new Image()
		document.images[i].l.src=document.images[i].src
		document.images[i].h=new Image()
		document.images[i].h.src=document.images[i].src.split('_l.')[0]+'_h.'+document.images[i].src.split('_l.')[1]
		document.images[i].onmouseover=function(){this.src=this.h.src}
		document.images[i].onmouseout=function(){this.src=this.l.src}

	}
}