var previousSelection = null;
  //Image Groups
  var HOME = '0';
  var COMPANY = '1';
  var SERVICE = '2';
  var RULES = '3';
  var FORMS = '4';
  var SERVER = '5';
  var INTL = '6';
  var NONE = null;

  //Image States
  var UP = '0';
  var DOWN = '1';

  /* Set nested array in following format
   * 0 = up
   * 1 = down
   */

  var jimagessrc = [
    ['images/homeup.gif', 'images/homedown.gif'],
    ['images/companyup.gif', 'images/companydown.gif'],
    ['images/serviceup.gif', 'images/servicedown.gif'],
    ['images/rulesup.gif', 'images/rulesdown.gif'],
    ['images/formsup.gif', 'images/formsdown.gif'],
    ['images/serverup.gif', 'images/serverdown.gif'],
    ['images/intlup.gif', 'images/intldown.gif']
  ];

  var jimages = new Array(jimagessrc.length);

  function cacheImages(){
    for(i=0; i<jimagessrc.length; i++){
      jimages[i] = new Array(jimagessrc[i].length);
      for(x=0; x<jimagessrc[i].length; x++){
        image = new Image();
        image.src = jimagessrc[i][x];
        //alert("Preloaded " + jimagessrc[i][x]);
        jimages[i][x] = image;
      }
    }
  }



  function revert(){highlight(previousSelection);}

  function select(selection){
    highlight(selection);
    switch(selection){
      case '0':
        previousSelection = HOME;
        break;
      case '1':
        previousSelection = COMPANY;
        break;
      case '2':
        previousSelection = SERVICE;
        break;
      case '3':
        previousSelection = RULES;
        break;
      case '4':
        previousSelection = FORMS;
        break;
      case '5':
        previousSelection = SERVER;
        break;
      case '6':
        previousSelection = INTL;
        break;
      default:
        previousSelection = null;
        break;
    }
  }

  function highlight(selection){

    //set all tabs to thier respective up -- inactive state

    document.Home.src= jimages[eval(HOME)][eval(UP)].src;
    document.Company.src= jimages[eval(COMPANY)][eval(UP)].src;
    document.Service.src= jimages[eval(SERVICE)][eval(UP)].src;
    document.Rules.src= jimages[eval(RULES)][eval(UP)].src;
    document.Forms.src= jimages[eval(FORMS)][eval(UP)].src;
    document.Server.src= jimages[eval(SERVER)][eval(UP)].src;
    document.Intl.src = jimages[eval(INTL)][eval(UP)].src;

    //set the the selected tab to its down -- active state

    switch(selection){
      case '0':
        document.Home.src = jimages[eval(HOME)][eval(DOWN)].src;
        break;
      case '1':
        document.Company.src = jimages[eval(COMPANY)][eval(DOWN)].src;
        break;
      case '2':
        document.Service.src = jimages[eval(SERVICE)][eval(DOWN)].src;
        break;
      case '3':
        document.Rules.src = jimages[eval(RULES)][eval(DOWN)].src;
        break;
      case '4':
        document.Forms.src = jimages[eval(FORMS)][eval(DOWN)].src;
        break;
      case '5':
        document.Server.src = jimages[eval(SERVER)][eval(DOWN)].src;
        break;
      case '6':
        document.Intl.src = jimages[eval(INTL)][eval(DOWN)].src;
        break;
      default:
        break;
    }
  }