I have a problem, I registered on CoinWorker four days ago and checked the tasks about 25 times a day, but every time I check there is only one task in the list which is for Japan (I live nowhere near Japan).
Sorry about that. I believe the tasks back-end is using IP address to control task availability.
Is there a chance your internet-provider routes things through Japan? (For example, what does an online service like
http://www.maxmind.com/app/locate_my_ip report as your approximate location using IP to guess?)
{Warge