No way to connect to mysql database with an existing user from the SQL map-broker wizard(or any mysql tool):

Access denied for user 'sepaconv'@'jpouget-d630.dhcp.phx.us.sopra' (using password: YES)

the user was not well defined in the mysql database.
the issue can be solved by applying the following commands on the mysql database:

This statement updates the user ¿sepaconv¿ to be accept logins from any host:
UPDATE `user` SET `host` = '%' WHERE `host` = 'rs37.ancy.fr.sopra' and `user` = 'sepaconv';

This statement causes MySQL to reload its privileges:
FLUSH PRIVILEGES;