if (document.images) {

    homeup       = new Image();
    homeup.src   = "images/home.gif";
    homedown     = new Image() ;
    homedown.src = "images/home_over.gif";		
	
	backup       = new Image();
    backup.src   = "images/back.gif";
    backdown     = new Image() ;
    backdown.src = "images/back_over.gif";	
	
	nextup       = new Image();
    nextup.src   = "images/next.gif";
    nextdown     = new Image() ;
    nextdown.src = "images/next_over.gif";	
}
function buttondown( buttonname ) {
    if (document.images) {
      document[ buttonname ].src = eval( buttonname + "down.src" );
    }
}
function buttonup ( buttonname ) {
    if (document.images) {
      document[ buttonname ].src = eval( buttonname + "up.src" );
    }
}
function MM_preloadImages() { //v3.0
  var d=document; if(d.images){ if(!d.MM_p) d.MM_p=new Array();
    var i,j=d.MM_p.length,a=MM_preloadImages.arguments; for(i=0; i<a.length; i++)
    if (a[i].indexOf("#")!=0){ d.MM_p[j]=new Image; d.MM_p[j++].src=a[i];}}
}
function preload() {
	MM_preloadImages('images/home_over.gif','images/home_over.gif','images/next_over.gif');
}