Due to the fact that Cingular uses NAT for GPRS customers, every customer is behind the same IP address (or small handfull of addresses.)

Last night I went to send an email through Yahoo's SMTP server and got this message:

"Data command failed: 521. yahoo.com closing transmission channel. Remote IP is over the limit for messages allowed to be sent in a single day."

I understand the idea behind what Yahoo has done, but don't they know what trouble this spells for any large entity with a lot of customers behind 1 IP address?

Anyone have any idea how to get a hold of someone in Yahoo to have them fix this problem?

I've been forced to find another SMTP server, but I'd like to be able to use Yahoo.