Warning "Udefined index dbname" while creating database with oci8 driver

In config specified:

doctrine:
dbal:
driver: "oci8"
host: "localhost"
port: "1521"
dbname: "orcl50"
user: "SYSTEM"
password: "123456"
charset: UTF8

When i create database (with symfony 2, doctrine:database:create), got that error:

=====================================
Could not create database for connection named orcl50
Notice: Undefined index: dbname in /path/to/symfony/vendor/doctrine-dbal/lib/Doctrine/DBAL/Driver/OCI8/Driver.php line 67
=====================================

If i comment "unset($params['dbname'])" in CreateDatabaseDoctrineCommand.php:54 all works fine.