From the sendmail FAQ, the following may or may not help explain the issue:

With no flags, sendmail reads its standard input up to an end-of-file or a line consisting only of a single dot and sends a copy of the message found there to all of the addresses listed. It determines the network(s) to use based on the syntax and contents of the addresses.

Local addresses are looked up in a file and aliased appropriately. Aliasing can be prevented by preceding the address with a backslash. Normally the sender is not included in any alias expansions, e.g., if `john' sends to `group', and `group' includes `john' in the expansion, then the letter will not be delivered to `john'.

-t Read message for recipients. To:, Cc:, and Bcc: lines will be scanned for recipient addresses. The Bcc: line will be deleted before transmission. Any addresses in the argument list will be suppressed, that is, they will not receive copies even if listed in the message header.

This doesn't really make it clear to me why -t is dangerous or why you'd be getting an error, however. What error are you getting?

EDIT: Hah, we all missed the obvious and tilly found it :)

In reply to Re: E-Mail responder by TedPride
in thread E-Mail responder by good2cu

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