.mailfilter allegedly 'Missing'

Hi
Wondering if someone could give any clue as to why Mail is not being
delivered...I have checked with the fetchmail list prior to
checking here. This is all running on a QNAP NAS device. Dovecot is running.

I am invoking fetchmail 6.3.21 with:
su - mdtesting -c '/opt/bin/fetchmail -vvv -f /opt/etc/fetchmailrc -m
"/opt/bin/maildrop -d %T"'

which gives this message on startup:
fetchmail: Old UID list from mydomain.com.au: <empty>
fetchmail: Scratch list of UIDs: <empty>


anyway, fetchmail runs but mail is not delivered via maildrop, with the
fetchmail log advising:

fetchmail: starting fetchmail 6.3.21 daemon
fetchmail: 6.3.21 querying mydomain.com.au (protocol POP3) at Sun Jan 20
23:28:33 2013: poll started
fetchmail: Trying to connect to mydomainipaddress/110...connected.
fetchmail: POP3< +OK Dovecot ready.
fetchmail: POP3> CAPA
fetchmail: POP3< +OK
fetchmail: POP3< CAPA
fetchmail: POP3< TOP
fetchmail: POP3< UIDL
fetchmail: POP3< RESP-CODES
fetchmail: POP3< PIPELINING
fetchmail: POP3< STLS
fetchmail: POP3< USER
fetchmail: POP3< SASL PLAIN
fetchmail: POP3< .
fetchmail: POP3> USER md
fetchmail: POP3< +OK
fetchmail: POP3> PASS *
fetchmail: POP3< +OK Logged in.
fetchmail: selecting or re-polling default folder
fetchmail: POP3> STAT
fetchmail: POP3< +OK 1 788
fetchmail: POP3> UIDL
fetchmail: POP3< +OK
fetchmail: POP3< 1 000034a1473af362
fetchmail: 1 is unseen
fetchmail: POP3< .
fetchmail: 1 message for md at mydomain.com.au (788 octets).
fetchmail: POP3> LIST 1
fetchmail: POP3< +OK 1 788
fetchmail: POP3> TOP 1 99999999
fetchmail: POP3< +OK
fetchmail: reading message [email protected]:1 of 1 (788 octets)About to
rewrite Return-Path: <[email protected]>...
...rewritten version is Return-Path: <[email protected]>.
fetchmail: About to rewrite From: [email protected]...
...rewritten version is From: [email protected].
fetchmail: About to rewrite To: [email protected]...
...rewritten version is To: [email protected].
fetchmail: about to deliver with: /opt/bin/maildrop -d 'mdtesting'
.mailfilter(39): Missing )
fetchmail: MDA returned nonzero status 75
fetchmail:  not flushed
fetchmail: POP3> QUIT
fetchmail: POP3< +OK Logging out.
fetchmail: 6.3.21 querying mydomain.com.au (protocol POP3) at Sun Jan 20
23:28:37 2013: poll completed
fetchmail: New UID list from mydomain.com.au: 000034a1473af362 = UNSEEN
fetchmail: swapping UID lists
fetchmail: sleeping at Sun Jan 20 23:28:37 2013 for 300 seconds


Other notes:
/opt/bin/maildrop has the SUID bit set

Mail will deliver if postfix is set as the delivery agent, rather than
maildrop

I have no idea why .mailfilter cant be found...its definitely in the $HOME
dir of 'mdtesting' ie
/share/MD0_data/new_home/mdtesting/.mailfilter

I added the 'uidl' parameter to fetchmailrc, which at least seems to have
fixed the 'LAST' error:
POP3> LAST
fetchmail: POP3< -ERR Unknown command: LAST

viz the relevant part of fetchmailrc:
set postmaster admin
set no bouncemail
poll mydomain.com.au service 110 protocol pop3 uidl
user "md" password "mypassword" is "mdtesting" here




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