Rt-mailgate not delivering mail

My RT install has been running fine for a couple of years until a recent
routine upgrade of the packages. Since then, no mail has been able to
get to RT.
I tested with
cat /usr/bin/test |/etc/smrsh/rt-mailgate --queue sales --action
correspond --url http://mail.globaltradinglimited.com/rt

and the result was

RT server error.

The RT server which handled your email did not behave as expected. It

Can’t use an undefined value as an ARRAY reference at
/opt/rt3/lib/RT/EmailParser.pm line 624.


Can anyone shed light on the solution?

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