      <!-- Beginning of JavaScript

      // *** BROWSER VERSION ***

      // convert all characters to lowercase to simplify testing

      var agt=navigator.userAgent.toLowerCase();

      // Note: On IE5, these return 4, so use is_ie5up to detect IE5.
      var is_major = parseInt(navigator.appVersion);

      // Note: Opera and WebTV spoof Navigator.  We do strict client detection.
      // If you want to allow spoofing, take out the tests for opera and webtv.
      var is_nav 
          = (    (agt.indexOf('mozilla')!=-1) && (agt.indexOf('spoofer')==-1)
              && (agt.indexOf('compatible') == -1) && (agt.indexOf('opera')==-1)
              && (agt.indexOf('webtv')==-1) && (agt.indexOf('hotjava')==-1));
      var is_nav4down = (is_nav && (is_major <= 4));
      var is_nav6up = (is_nav && (is_major >= 5));

      var is_ie  = ((agt.indexOf("msie") != -1) 
                                               && (agt.indexOf("opera") == -1));
      var is_ie3 = (is_ie && (is_major < 4));
      var is_ie4 = (is_ie && (is_major == 4) && (agt.indexOf("msie 5")==-1));

      var is_ie5 = (is_ie && (is_major == 4) && (agt.indexOf("msie 5.0")!=-1) );
      var is_ie6 = (is_ie && (is_major == 4) && (agt.indexOf("msie 6")!=-1) );
      var is_ie5_5up =(is_ie && !is_ie3 && !is_ie4 && !is_ie5) || is_ie6;

      // Platform.

      var is_mac    = (agt.indexOf("mac")!=-1);
      var is_win   = ( (agt.indexOf("win")!=-1) || (agt.indexOf("16bit")!=-1) );

      // End of JavaScript -->