I have noticed that Zend_Locale throws an exception with the message "Autodetection of Locale has been failed!" when used with Zend_Rest_Server and Zend_Rest_Client.

Here is my setup...

Server A - Zend_Rest_Server instance. - Exception thrown when using $date = new Zend_Date(); within a rest controller.

Server B - Zend_Rest_Client initiates request to Server A.

I have also noticed this problem with visitors to my site. It is infrequent but a real bug that is causing some browsers to die when the exception is thrown.