.ui-autocomplete {
        max-height: 200px;
        overflow-y: auto;
        /* prevent horizontal scrollbar */
        overflow-x: hidden;
        /* add padding to account for vertical scrollbar */
        padding-right: 20px;        
    }

    .ui-autocomplete-input {
       
    }

       /* IE 6 doesn't support max-height
    * we use height instead, but this forces the menu to always be this tall
    */
       * html .ui-autocomplete {
           height: 200px;
       }