Php – “session has already been started….” exception in Zend Framework application

I get this error when trying to load a Zend Framework application:

Fatal error: Uncaught exception
'Zend_Session_Exception' with message
'session has already been started by
session.auto-start or session_start()'
in
/www/htdocs/w00a1ed7/autospin/redaktion/library/Zend/Session.php:462

Stack trace:

#0 /www/htdocs/w00a1ed7/autospin/redaktion/library/Zend/Session/Namespace.php(143):
Zend_Session::start(true)

#1 /www/htdocs/w00a1ed7/autospin/redaktion/library/Zend/Auth/Storage/Session.php(87):
Zend_Session_Namespace->__construct('Zend_Auth')

#2 /www/htdocs/w00a1ed7/autospin/redaktion/library/Zend/Auth.php(91):
Zend_Auth_Storage_Session->__construct()

#3 /www/htdocs/w00a1ed7/autospin/redaktion/library/Zend/Auth.php(141):
Zend_Auth->getStorage()

#4 /www/htdocs/w00a1ed7/autospin/redaktion/application/layouts/scripts/layout.phtml(31):
Zend_Auth->hasIdentity()

#5 /www/htdocs/w00a1ed7/autospin/redaktion/library/Zend/View.php(108):
include('/www/htdocs/w00…')

#6 /www/htdocs/w00a1ed7/autospin/redaktion/library/Zend/View/Abstract.php(831):
Zend_View->_run('/www/htdocs/w00…')

#7 /www/htdocs/w00a1ed in /www/htdocs/w00a1ed7/autospin/redaktion/library/Zend/Session.php
on line 462

I Use Zend_Auth and on my local server and it works well, but on a production server I get the preceding error, but not every time.

I have checked that session.autostart is set to 0 in the .htaccess file.

How do I fix this error?

Thank you for your Answer, but I do not user session_start() anywhere. Work only with ZF.

I Have this Problem only on shared server, on my local server script works perfectly.

I Use INIT Function with this code:

protected $user;

public function init()
{   
    if(!Zend_Auth::getInstance()->hasIdentity())
    {
        $this->_redirect('auth/login');
    }else
    {
        $this->user = Zend_Auth::getInstance()->getIdentity();
    }
}

I allready try to set tis code only in indexAction, so that other actions do not have to chack the Auth… but still have problems.

Ist there a way to set in an Action to do not check about session or somethink like this?

Beste regards