RabbitMQ Java connection throws UnknownHostException: invalid IPv6 address

A very simple connection, the RabbitMQ broker has Public accessibility= Yes
On factory.newConnection(),, using Java1.8 & amqp-client-5.12.0.jar (latest), getting the above exception.
//factory is set:
factory.setUsername(queueUser);
factory.setPassword(queuePassword);
factory.setVirtualHost("/");
factory.setHost(queueHost);
factory.setPort(5671);
and the queueHost is set to the AMQP Endpoints on the RabbitMQ console.
This should be a 5 minutes setup, but I already spent way too much time on this.
I have not set this broker, nor do I see how to set it, with IPv6. I just need simple Ipv4 to work.
Any idea ?