function enableTab( tab, tab_label ) {

      document.getElementById( tab ).className = "selected";
      document.getElementById( tab_label ).className = "selected";

   	  document.getElementById( 'tabset_box' ).style.visibility = "visible";

  }

  function showHint( hint ) {

      document.getElementById( "hint" ).innerHTML = hint;
  }

  function onLoad() {

      if (document.getElementById( "tab1" ).innerHTML != "")
          document.getElementById( "tab_label1" ).className = "unselected";

      if (document.getElementById( "tab2" ).innerHTML != "")
          document.getElementById( "tab_label2" ).className = "unselected";

      if (document.getElementById( "tab3" ).innerHTML != "")
          document.getElementById( "tab_label3" ).className = "unselected";

      if (document.getElementById( "tab4" ).innerHTML != "")
          document.getElementById( "tab_label4" ).className = "unselected";

      if (document.getElementById( "tab1" ).innerHTML != "")
          enableTab( 'tab1', 'tab_label1' );
	  else if (document.getElementById( "tab2" ).innerHTML != "")  
          enableTab( 'tab2', 'tab_label2' );
	  else if (document.getElementById( "tab3" ).innerHTML != "") 
          enableTab( 'tab3', 'tab_label3' );
	  else if (document.getElementById( "tab4" ).innerHTML != "") 
          enableTab( 'tab4', 'tab_label4' );

  }