[exim] mysql_servers

Hi All,

I use Exim 4.12 and I use MySQL database for mail users.
When I start the server I got the following error message:
----------------------
Exim configuration error
main option "mysql_servers" unknown in line 50
----------------------

I configured the MySQL server parameters corresponding to the documentation:
hide mysql_servers = localhost/users/root/secret

What could be the problem?

Best regards,
Janos