Assign virtualmin User to mysql database as Virtualserver administrator not working Version 6.01

Well, i am having the folloing problem.

Virtualmin GPL installation over a Ubuntu 14.04 and many virtual servers for clients.

Before the 6.01 Update:
Any virtual server administrator with permissions to create databases had a list of databases of his virtual server in create/edit user form. He selected (move from left to right) any database, and then the user of virtualmin/email had a new mysql user authentication and permissions over the selected database.

After the update:
The widget with the databases is already in the user form, but when i add a database to any user using a virtualmin account (not the the superadmin one), the result is the next error:

Failed to save user : DBI connect failed : Access denied for user ‘domain.tld’@‘localhost’ to database ‘mysql’

Is there anything users/admin must know to recover the old behaviour?

Thank you very much.