/**
        * @author Alexander Farkas
        * v. 1.02
        */
        (function($) {
        $.extend($.fx.step,{
        backgroundPosition: function(fx) {
        if (fx.state === 0 && typeof fx.end == 'string') {
		var start = jQuery.curCSS(fx.elem, 'backgroundPosition'); 
                if (!start) { 
                    start = jQuery.curCSS(fx.elem, 'backgroundPositionX') + ' ' + jQuery.curCSS(fx.elem, 'backgroundPositionY'); 
                } 
         start = toArray(start);
         fx.start = [start[0],start[2]];
         var end = toArray(fx.end);
         fx.end = [end[0],end[2]];
         fx.unit = [end[1],end[3]];
         }
         var nowPosX = [];
         nowPosX[0] = ((fx.end[0] - fx.start[0]) * fx.pos) + fx.start[0] + fx.unit[0];
         nowPosX[1] = ((fx.end[1] - fx.start[1]) * fx.pos) + fx.start[1] + fx.unit[1];
         fx.elem.style.backgroundPosition = nowPosX[0]+' '+nowPosX[1];

         function toArray(strg){
         strg = strg.replace(/left|top/g,'0px');
         strg = strg.replace(/right|bottom/g,'100%');
         strg = strg.replace(/([0-9\.]+)(\s|\)|$)/g,"$1px$2");
         var res = strg.match(/(-?[0-9\.]+)(px|\%|em|pt)\s(-?[0-9\.]+)(px|\%|em|pt)/);
         return [parseFloat(res[1],10),res[2],parseFloat(res[3],10),res[4]];
         }
         }
         });
        })(jQuery);