What's wrong with 5.1.2 and 5.1.8 ?
X.1.2 Bad destination system address
The destination system specified in the address does not exist
or is incapable of accepting mail. For Internet mail names,
this means the address portion to the right of the "@" is
invalid for mail. This code is only useful for permanent
failures.
X.1.8 Bad sender's system address
The sender's system specified in the address does not exist or
is incapable of accepting return mail. For domain names, this
means the address portion to the right of the "@" is invalid
for mail.
Those look right to me. Will adjust accordingly.
Regards,
John Levine, johnl(_at_)taugh(_dot_)com, Taughannock Networks, Trumansburg NY
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