Using Compuserve With Mac Os X

[cdwrite]

I am using Mac OS X 10.3.9 on an iBook G4. Because I operate an email news subscription service with over 12,000 clients, I require an ISP which permits unlimited emails. I therefore use CompuServe combined with Microsoft Entourage. This worked reliably on my only iBook G3 under OS 9.2, but with OS X I can send emails, but cannot receive them. I have to use my old G3 iBook to receive replies. I have read some forum exchanges suggesting that CompuServe can resolve this by issuing a new POP3 password, but the UK helpline, on the rare occasions when one can even get a reply, does not appear to manned by any personnel who understand this problem. Can anyone suggest a solution? Either I need to receive CompuServe messages on my iBook G4, or I need an alternative ISP which permits unlimited outgoing emails. Please note that I already have accounts with Gmail and Mac.com, both of which promise unlimited emails but which actually limit me to 400 messages per 24 hours - not much use when trying to send 12,000.