Caching issue

	function SessionHandler($directive)
	{
		global $modx;
				
		if (!empty($this->Report))
		{
			return; //There was an error in the last step
		}
		
		$cookieName = 'WebLoginPE';
		
		if ($directive == 'start') 
		{
			$_SESSION['webShortname'] = $this->Username; 
		    $_SESSION['webFullname'] = $this->User['fullname']; 
		    $_SESSION['webEmail'] = $this->User['email']; 
		    $_SESSION['webValidated'] = 1; 
		    $_SESSION['webInternalKey'] = $this->User['internalKey']; 
		    $_SESSION['webValid'] = base64_encode($this->Password); 
		    $_SESSION['webUser'] = base64_encode($this->Username); 
		    $_SESSION['webFailedlogins'] = $this->User['failedlogincount']; 
		    $_SESSION['webLastlogin'] = $this->User['lastlogin']; 
		    $_SESSION['webnrlogins'] = $this->User['logincount'];
		    $_SESSION['webUserGroupNames'] = ''; // reset user group names
			
			$cookieValue = md5($this->User['username']).'|'.$this->User['password'];
			
			if ($_POST['rememberme'] == 'on')
			{
				$cookieExpires = time() + (60 * 60 * 24 * 365 * 5); //5 years
				
				setcookie($cookieName, $cookieValue, $cookieExpires, '/', $_SERVER['SERVER_NAME'], 0);
		    }
			
			if (isset($_POST['stayloggedin']) && $_POST['stayloggedin'] !== '')
			{
				$cookieExpires = time() + $_POST['stayloggedin'];
				
				setcookie($cookieName, $cookieValue, $cookieExpires, '/', $_SERVER['SERVER_NAME'], 0);
			}
		}
		
		if ($directive == 'destroy')
		{
			// if we were launched from the manager do NOT destroy session !!!
	        if (isset($_SESSION['mgrValidated']))
			{
	            unset($_SESSION['webShortname']);
	            unset($_SESSION['webFullname']);
	            unset($_SESSION['webEmail']);
	            unset($_SESSION['webValidated']);
	            unset($_SESSION['webInternalKey']);
	            unset($_SESSION['webValid']);
	            unset($_SESSION['webUser']);
	            unset($_SESSION['webFailedlogins']);
	            unset($_SESSION['webLastlogin']);
	            unset($_SESSION['webnrlogins']);
	            unset($_SESSION['webUsrConfigSet']);
	            unset($_SESSION['webUserGroupNames']);
	            unset($_SESSION['webDocgroups']);   
	        }
	        else
			{
				setcookie(session_name(), '', 0, $modx->config['base_url']);
	        }
			
			setcookie($cookieName, '', time()-60, '/', $_SERVER['SERVER_NAME'], 0);
		}
	}

if (isset($_COOKIE[session_name()])) {setcookie(session_name(), '', 0, $modx->config['base_url']);}

setcookie(session_name(), '', 0, $modx->config['base_url']);

  # apply JavaScript patch only if the request comes from IE browser
  if (strpos($_SERVER['HTTP_USER_AGENT'], 'MSIE')) {
      #### original piece of code #
      $modx->regClientStartupScript('assets/snippets/webloginpe/js/ieButtonFix.js');
      # original piece of code ####
  }