Session database not working, using cookies does

[eluser]mariek[/eluser]
Hi all,
with a new version of MySQL, more strict, a NOT NULL field have to be set. It's like in Postgres.
So the second option (besides downgrading Mysql) is to set the user_data field to NULL as suggested here :
http://ellislab.com/forums/viewthread/94940/

Regards,