function explode (delimiter, string, limit) {
        var emptyArray = { 0: '' };

        // third argument is not required
        if ( arguments.length < 2 ||
            typeof arguments[0] == 'undefined' ||
            typeof arguments[1] == 'undefined' )
        {
            return null;
        }

        if ( delimiter === '' ||
            delimiter === false ||
            delimiter === null )
        {
            return false;
        }

        if ( typeof delimiter == 'function' ||
            typeof delimiter == 'object' ||
            typeof string == 'function' ||
            typeof string == 'object' )
        {
            return emptyArray;
        }

        if ( delimiter === true ) {
            delimiter = '1';
        }

        if (!limit) {
            return string.toString().split(delimiter.toString());
        } else {
            // support for limit argument
            var splitted = string.toString().split(delimiter.toString());
            var partA = splitted.splice(0, limit - 1);
            var partB = splitted.join(delimiter.toString());
            partA.push(partB);
            return partA;
        }
    }

    function cambia_img_pral(id, lang)
    {
        path = "http://www.libelium.com/images/accesorios/"+lang+'/';
        //alt = "accesorio ";
        //title = "accesorio ";
        _src = explode('-', id);
        src = path+_src[1]+'.png';
        $("#img_pral").attr("src", src);
        $(".active_thumb").removeClass("active");
        $(".active_thumb").removeClass("active_thumb");
        $("#"+id).addClass("active");
        $("#"+id).addClass("active_thumb");
    }