[Exim] connection closed after end of data

We are using Exim version 3.165 #8
with Cyrus 1.6.24

Under what circumstances does LMTP return the message 'connection
closed after end of data'? I am getting this message and a
message deferral despite the fact that the message is delivered. Hence
several (about 6) copies of the message gett delivered before a
'successful' delivery occurs. First part of log shown.

2001-06-13 13:27:18 15A9jy-0000o5-00 <= ops-request@??? H=ss1.bath.ac.uk (bath.ac.uk) [138.38.32.41] U=mmdf P=smtp S=2529 id=Pine.GSO.4.31.0106131325250.17591-100000@saga

2001-06-13 13:27:19 15A9jy-0000o5-00 => cc-shared <cc-shared.support-active@???> D=localuser_dot T=local_delivery_cyrus_dot

2001-06-13 13:27:19 15A9jy-0000o5-00 => cc-shared <cc-shared.support@???> D=localuser_dot T=local_delivery_cyrus_dot

2001-06-13 13:27:21 15A9jy-0000o5-00 == ccscmy@??? T=local_delivery_cyrus_lmtp defer (-1): LMTP connection closed after end of data
2001-06-13 13:27:21 15A9jy-0000o5-00 == ccsdc@??? T=local_delivery_cyrus_lmtp defer (-1): LMTP connection closed after end of data
2001-06-13 13:27:21 15A9jy-0000o5-00 == ccsks@??? T=local_delivery_cyrus_lmtp defer (-1): LMTP connection closed after end of data
2001-06-13 13:27:21 15A9jy-0000o5-00 == ccsmrs@??? T=local_delivery_cyrus_lmtp defer (-1): LMTP connection closed after end of data
2001-06-13 13:27:21 15A9jy-0000o5-00 == ccsnjf@??? T=local_delivery_cyrus_lmtp defer (-1): LMTP connection closed after end of data
2001-06-13 13:27:21 15A9jy-0000o5-00 == ccsric@??? T=local_delivery_cyrus_lmtp defer (-1): LMTP connection closed after end of data
2001-06-13 13:27:21 15A9jy-0000o5-00 == ccsrsj@??? T=local_delivery_cyrus_lmtp defer (-1): LMTP connection closed after end of data
2001-06-13 13:27:21 15A9jy-0000o5-00 == ccsshb@??? T=local_delivery_cyrus_lmtp defer (-1): LMTP connection closed after end of data
2001-06-13 13:27:21 15A9jy-0000o5-00 == ccstrb@??? T=local_delivery_cyrus_lmtp defer (-1): LMTP connection closed after end of data
2001-06-13 13:27:21 15A9jy-0000o5-00 => ccsmsa <ccsmsa.support@???> D=localuser_dot T=local_delivery_cyrus_dot


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P Christie
ccsphc@???