They'll get it faster. They wrote me same stuff about 2-3 weeks once and after 5 days packed and sent my cd. 3-4 weeks thats the worst case. Don't be upset.
CD Japan can be kinda slow though. Availibility on their page says 3-7 days but once you order they get back to you after a few days saying "Hey, it will take us 3 weeks to get this itrem!". Happened to me before more than once.