Godaddy Sux. I just left them recently for 1and1.com
Godaddy uses VERY aggressive filtering on the email servers, and I was loosing email without being told it was being dumped. After about a year, I figured out the pattern, brought it to the attention of customer service, and after a few weeks of pressing my case to get past dummy level one, I finally got an officer of the company.
The end result: tough. This is the way we do it. Sorry.
Bye Bye Godaddy. 1and1 was cheaper too and now *I* control all filtering options, which I keep turned off.
Now the mail that used to get dumped comes right through.