[horde] Problem with session_start()

[lst_hoe02 at kwsoft.de]

Zitat von Jan Schneider <jan at horde.org>:

> Zitat von lst_hoe02 at kwsoft.de:
>
>> Hello,
>>
>> since recently we have a lot of the following in our logfile:
>>
>> Dec 17 11:33:41 ftp HORDE: PHP ERROR: session_start(): The session  
>> id is too long or contains illegal characters, valid characters are  
>> a-z, A-Z, 0-9 and '-,' [pid 32572 on line 69 of  
>> "/usr/share/php/Horde/Session/Null.php"]
>>
>> any idea what to fix to get this work?
>>
>> Horde/IMP are all latest and PHP settings are mostly default.
>
> And what *is* the id?
>

How to find out? It is not logged as far as i can see...
Should it be listed in the admin panel? I guess no because it is  
rejected after all...

Thanks

Andreas