While you could probably program Sendmail to do the Right Thing for all modes of operation, the effort would not be worth it. Some, such as Netscape Communicator or KMail, have client implementations of the necessary network mail protocols built in. In that case, use those, and point them to your ISP mail servers. Pine, another popular choice, can use your SMTP relay for sending, but reads your local Unix mailbox. If you need help with fetchmail, give a yell.
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