[EXIM] Strange behaviour with .forward files in Exim 1.92

Running Exim 1.92 on a Dec alpha with Digital UNIX V4.0D, I have noticed
what
seems to be curious behaviour with forwarding.

The forward file

\alan
alan@sernt7

does exactly what I would expect ... mail to the 2 machines

But the forward file

\alan
alan@???

does not work. Mail is not forwarded to the remote machine.

Has anyone ever seen similar behaviour, or can suggest how I have
misconfigured things?


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