Yes i am having that problem too. and Nintendo Support is driving me mad, Ive rung them 3 times about it. The last two times Ive been told that 'They are looking into it' and that they 'have checked my account and it all seems fine'..which is utter crap because the only info ive they've taken from me so far is my first name and phone number.
Glad to hear its not just me though, it means they'll have to figure it out sooner or later, Ive had days when ive gotten more than 15 of them, i get them whenever i turn the system off
14/01/2007
Geelong, Victoria