Migration to MariaDB 10.0 fails

Hello!

I'm not sure whether this is a bug or simply an error occuring in my system only.

I want to migrate to MariaDB 10.0 and follow the best practice guide from MariaDB.
In detail I executed the following steps:

• Start Ubuntu in recovery mode
• Stop service mysql
• Start installation of mariadb-server

The installation will automatically remove mysql-server-5.5 and all depending packages.

However, the configuration of package mariadb-server-10.0 fails with this error:
trying to overwrite '/usr/share/mysql/mysql_system_tables.sql, which is also in package mysql-server-core-5.5
(All details in attached screenshot).

How can I fix this problem?

THX