It is true!
Sasha (my dog) had her test done in Aug 20th/07. We relocated to England on Nov 26th/07, so 3 months have passed, and sadly she will have to stay in quaratine until Feb 19th/08.
I must agree with Dar... if you can complete the 6 month period in the US, PLEASE DO SO!!! Your dog will be confined to a really small space, with no possibilities of walks, and most of the quarantine kennels have very short visit times.
Hope it helps!