Bignige - 2013-03-04

I am trying to enable spamassassin spam checking using a pipe through spamc & dovecot deliver. the email is being checked but not delivered to recipient because of 'user unknown'

see log entrys:

Mar 4 10:41:47 master postfix/smtpd[23430]: connect from cad2.MYDOMAIN[192.168.0.3]
Mar 4 10:41:47 master postfix/smtpd[23430]: BDBE52029A: client=cad2.MYDOMAIN[192.168.0.3]
Mar 4 10:41:47 master postfix/cleanup[23433]: BDBE52029A: message-id=<51347A1A.3090103@MYDESTINATION.com
Mar 4 10:41:47 master postfix/qmgr[22588]: BDBE52029A: from=n.kilner@MYDESTINATION.com, size=728, nrcpt=1 (queue active)
Mar 4 10:41:47 master postfix/smtpd[23430]: disconnect from cad2.MYDOMAIN[192.168.0.3]
Mar 4 10:41:47 master spamd[23904]: spamd: connection from localhost [127.0.0.1] at port 51775
Mar 4 10:41:47 master spamd[23904]: spamd: setuid to nigel succeeded
Mar 4 10:41:47 master spamd[23904]: spamd: processing message 51347A1A.3090103@MYDESTINATION.com for nigel:1000
Mar 4 10:41:48 master dovecot: imap(nigel): Disconnected: Disconnected in IDLE in=1334 out=2848
Mar 4 10:41:48 master dovecot: imap-login: Login: user=<nigel>, method=PLAIN, rip=192.168.0.3, lip=192.168.0.1,mpid=23438, TLS, session=<OVgFARfXjgDAqAAD>
Mar 4 10:41:58 master spamd[23904]: spamd: clean message (2.5/5.0) for nigel:1000 in 10.3 seconds, 807 bytes.
Mar 4 10:41:58 master spamd[23904]: spamd: result: . 2 - ALL_TRUSTED,DRUGS_ERECTILE,DRUGS_ERECTILE_OBFU,TVD_SPACE_RATIO scantime=10.3,size=807,user=nigel,uid=1000,required_score=5.0,rhost=localhost,raddr=127.0.0.1,rport=51775,mid=51347A1A.3090103@MYDESTINATION.com,autolearn=no
Mar 4 10:41:58 master postfix/pipe[23434]: BDBE52029A: to=nigel@MYDESTINATION.com, relay=spamassassin, delay=10, delays=0.06/0.02/0/10, dsn=5.1.1, status=bounced (user unknown)
Mar 4 10:41:58 master postfix/cleanup[23433]: 3D21A202B3: message-id=20130304104158.3D21A202B3@master.MYDOMAIN.co.uk
Mar 4 10:41:58 master postfix/bounce[23441]: BDBE52029A: sender non-delivery notification: 3D21A202B3
Mar 4 10:41:58 master postfix/qmgr[22588]: 3D21A202B3: from=<>, size=2693, nrcpt=1 (queue active)
Mar 4 10:41:58 master postfix/qmgr[22588]: BDBE52029A: removed
Mar 4 10:41:58 master postfix/local[23443]: 3D21A202B3: to=nigel@MYDESTINATION.com, orig_to=n.kilner@MYDESTINATION.com, relay=local, delay=0.15, delays=0.03/0.03/0/0.09, dsn=2.0.0, status=sent (delivered to command: IFS=' ' && exec /usr/bin/procmail -f- || exit 75 #nigel)
Mar 4 10:41:58 master postfix/qmgr[22588]: 3D21A202B3: removed

here is my master.cf entry fot the pipe:

spamassassin unix - n n - - pipe
flags=DRhu user=spamd:spamd argv=/usr/bin/spamc -u ${user} -e /usr/lib/dovecot/deliver -d ${recipient}

has anyone else encountered a similar problem? I have searched for a solution but not found anything which helps.

What do I need to check to find a solution?

Bignige