function btn_change ()
{
   var rem, keep=0, store, obj, switcher = new Array, history = document.Data;
   for ( rem = 0; rem < ( btn_change.arguments.length - 2 ); rem += 3 )
   {
      store = btn_change.arguments [ ( navigator.appName == 'Netscape' ) ? rem : rem + 1 ];
      if (( store.indexOf ( 'document.layers[' ) == 0 && document.layers == null ) ||
          ( store.indexOf ( 'document.all[' ) == 0 && document.all == null ))
         store = 'document' + store.substring ( store.lastIndexOf ( '.' ), store.length );

         obj = eval ( store );
         if ( obj != null )
         {
            switcher [ keep++ ] = obj;
            switcher [ keep++ ] = ( history == null || history [ keep - 1 ] != obj ) ? obj.src : history [ keep ];
            obj.src = btn_change.arguments [ rem + 2 ];
         }
   }
   document.Data = switcher;
}

function btn_restore ()
{
   if ( document.Data != null )
      for ( var rem = 0; rem < ( document.Data.length - 1 ); rem += 2 )
         document.Data [ rem ].src = document.Data [ rem + 1 ];
}