Erreur après mise à jour (2 replies)

Impossible de se connecter à Piwik après mise à jour proposé (1.12 je crois)

J'ai ce message au dessus de la fenêtre de login :

Erreur: You must call Zend_Session::regenerateId() before any output has been sent to the browser; output started in /var/www/piwik/libs/Zend/Log/Writer/Stream.php/133

Ainsi que :

There is an error. Please report the message (Piwik 1.12) and full backtrace in the Piwik forums (please do a Search first as it might have been reported already!).

Warning: preg_match(): Unknown modifier '/' in /var/www/piwik/core/Url.php on line 208

Backtrace -->

#0 Piwik_ErrorHandler(...) called at [:]
#1 preg_match(...) called at [/var/www/piwik/core/Url.php:208]
#2 Piwik_Url::isValidHost(...) called at [/var/www/piwik/core/Url.php:254]
#3 Piwik_Url::getHost(...) called at [/var/www/piwik/core/Url.php:283]
#4 Piwik_Url::getCurrentHost(...) called at [/var/www/piwik/core/Url.php:63]
#5 Piwik_Url::getCurrentUrlWithoutFileName(...) called at [/var/www/piwik/core/Piwik.php:170]
#6 Piwik::getPiwikUrl(...) called at [/var/www/piwik/core/FrontController.php:279]
#7 Piwik_FrontController->init(...) called at [/var/www/piwik/index.php:46]

et aussi

There is an error. Please report the message (Piwik 1.12) and full backtrace in the Piwik forums (please do a Search first as it might have been reported already!).

Warning: preg_match(): Unknown modifier '/' in /var/www/piwik/core/Url.php on line 208

Backtrace -->

#0 Piwik_ErrorHandler(...) called at [:]
#1 preg_match(...) called at [/var/www/piwik/core/Url.php:208]
#2 Piwik_Url::isValidHost(...) called at [/var/www/piwik/core/Url.php:254]
#3 Piwik_Url::getHost(...) called at [/var/www/piwik/core/Url.php:429]
#4 Piwik_Url::isLocalUrl(...) called at [/var/www/piwik/core/Nonce.php:71]
#5 Piwik_Nonce::verifyNonce(...) called at [/var/www/piwik/plugins/Login/Controller.php:62]
#6 Piwik_Login_Controller->login(...) called at [/var/www/piwik/plugins/Login/Controller.php:45]
#7 Piwik_Login_Controller->index(...) called at [:]
#8 call_user_func_array(...) called at [/var/www/piwik/core/FrontController.php:125]
#9 Piwik_FrontController->dispatch(...) called at [/var/www/piwik/core/Controller.php:681]
#10 Piwik_Controller->redirectToIndex(...) called at [/var/www/piwik/plugins/CoreHome/Controller.php:40]
#11 Piwik_CoreHome_Controller->redirectToCoreHomeIndex(...) called at [:]
#12 call_user_func_array(...) called at [/var/www/piwik/core/FrontController.php:125]
#13 Piwik_FrontController->dispatch(...) called at [/var/www/piwik/index.php:47]

et bien d'autre mais aucune connexion possible.

J'ai refait la mise à jour en manuel
et fait l'update/upgrade de mon serveur (ubuntu 12.04)