/**
* Zoekt de afbeeldingen met de class mouseover,
* preload de "mouseover" afbeelding en hangt de events aan de afbeeldingen
*/
var initMouseover = function()
{
   // zoek de afbeeldingen met de class mouseover
   YAHOO.util.Dom.getElementsByClassName("mouseover", "img", null, function( el ) {

       // preload over image
       var i = new Image();
       var len = el.src.length;
       var ext = el.src.substring( len - 3);
       i.src = el.src.substring( 0, len-4 ) + "_over." + ext;

       // evens toevoegen (mouseover, mouseout)
       YAHOO.util.Event.on( el, 'mouseover', function( e ) {
           var len = this.src.length;
           var ext = this.src.substring( len - 3);
           var end = this.src.substring( 0, len-4 );

           if( end.substring( end.length-5, end.length ) != '_over')
           {
               this.src = end + "_over." + ext;
           }
       });

       // evens toevoegen (mouseover, mouseout)
       YAHOO.util.Event.on( el, 'mouseout', function( e ) {
           var len = this.src.length;
           var ext = this.src.substring( len - 3);

           if( this.src.substring( len-9, len ) == '_over.' + ext )
           {
               this.src = this.src.substring( 0, len-9 ) + "." + ext;
           }
       });
   });
}
YAHOO.util.Event.on(window, "load", initMouseover );