Don't want anyone upset at me but I agree with Texasbluesplayer.
This line "Subtle variations in the manufacturing process from country to country" is a bit of B.S.
I'm from Canada and my unit is made in China as must be other people's units.
Now that you say that it's due to different policies, regulations and languages, I agree.
Also, I think there's a tendency for companies to release a product, support it for a few months and then move on to the next product, forgetting about the 1st one. As mentionned in other threads, US D-Link released the firmware update for the DNS-325 without mentionning that it would render the plugins from the 1st version useless. What's more, the WW plugins for the 2nd update have existed for a few months and there's still no mention of the them in the US site. Another example is that the DNS-325 is being sold as having an iTunes server, when it isn't even compatible with current versions of iTunes.
So sometimes you have to look outside "the box" but being careful as JavaLawyer as pointed out.