A friend purchased a DVD online and tried to play it on my one-year-old Panasonic DVD player. The unit wouldn't play the disk because the media was not region-4. I conducted a quick search online and discovered it's possible to configure the unit to be multi-region. I called Panasonic and they confirmed it can be configured by a Panasonic service agent. Panasonic provided the contact details for the nearest service centre. The service agent advised me to bring the unit to them, together with proof of purchase and the matching remote control. I did so and they configured the unit to be multi-region. It took around 10 minutes to do and they applied the change while I waited. This service was free of charge.
I haven't verified the facts, but the agent advised it is illegal to import region-free players into Australia, but it is not illegal to subsequently configure the units to be region-free. He indicated it's possible to make the standard DVD function region-free, but not Blu-Ray, which is locked down by Panasonic.
I gather they simply press a predefined sequence of buttons on the remote to enable region-free functionality. I see online that it's possible to do this with some Samsung units, but I don't know Samsung's policy on providing this as a service to customers.
In any event, the offending DVD can now be successfully played. I tested other region 4 and Blu-Ray DVDs, and they still play, so (as expected) the configuration change has had no detrimental impact.
I found this Panasonic web page, for New Zealand customers, advising their DVD or Blu-Ray units can be multi-zoned free of charge, and certain models can be multi-zoned by customers.
I rarely use the DVD player and am no aficionado so am unsure if the ability to make players region-free is widely known. However, I hope this post proves of value to other consumers.