[Dovecot] mysql authentication problems

Hello all..

I'm trying to configure dovecot do athenticate using mysql, but I?m having some troubles... After configuring the mysql athentication in dovecot-mysql.conf and in dovecot.conf, when I try to login I get this mesage in my logs:

Dovecot-auth: MySQL: Can't connect to database dovecot: Can't connect to local MySQL server through socket '/var/tmp/mysql.sock' (2)

Any ideia why this happens and how to fix it?

Thanks in advance,

Pedro