Been researching this problem too. I found this on another site.
"This is apperently due to Nokia routing the email via their servers. A way around this is to decline the terms of service when setting up a mail account. This should allow you to manually set up your account. This will bypass the Nokia servers and not impose the limit.
Unfortunatly if you have already setup your amil, the only known way is to factory reset your phone, and then go through mail setup as described. This is a major pain, and if anyone knows an easier way of doing this, please post it."
Right now still trying to find that "easier way" Can anyone offer us any advice?