Sophos Pure Message. Connection Refused.

Morning,

I am having an issue with my Sophos Pure Message Appliance.

When mail routing is configured to run through the Appliance I can send internal mail, and send mail externally. However any mail sent externally to our domain gets stopped. The logs are below.

Does anyone know why this would be happening.

The mail will eventually return it to the sender after two days saying the same as below. Connection Refused.

Thanks in advance for any assistance that can be provided.

2013-04-22 07:49:54
dave@ausnichols.net
nicd@btac.nsw.edu.au
192.168.10.1
192.168.10.106
Re: IT TEST MONDAY
Message-ID:
Sender: dave@ausnichols.net
Recipient(s): nicd@btac.nsw.edu.au
Direction: Inbound
Received: Connection from 192.168.10.1
Queued: For scanning at 2013-04-22 07:49:57
Scanned: With result: legitimate. Message will be delivered.
Removed: From scanning queue at 2013-04-22 07:50:04

Policy Rule: Checked Message Inbound
Sender: dave@ausnichols.net
Recipient(s): nicd@btac.nsw.edu.au
Queued: For delivery at 2013-04-22 07:50:04
Deferred: Connect to btacsvr22.btac.nsw.edu.au[192.168.10.106]:25: Connection refused at 2013-04-22 07:50:05
View log details...
Appliance: puremessagevirtual.btac.nsw.edu.au [192.168.10.52]


Detailed Log Section.

2013-04-22 07:49:54 puremessagevirtual postfix/smtpd[6794]: C8C6668AC8_1745F02F: client=unknown[192.168.10.1]
2013-04-22 07:49:55 puremessagevirtual postfix/cleanup[6842]: C8C6668AC8_1745F02F: message-id= 
2013-04-22 07:49:57 puremessagevirtual postfix/qmgr[2351]: C8C6668AC8_1745F02F: from=, size=13650, nrcpt=1 (queue active)
2013-04-22 07:50:04 puremessagevirtual postfix/smtp[6893]: C8C6668AC8_1745F02F: to=, relay=127.0.0.1[127.0.0.1]:10025, delay=9.9, delays=3.2/0.06/0/6.6, dsn=2.0.0, status=sent (250 OK, sent 51745F05_2001_2_1 534CF6B7AF_1745F0CB)
2013-04-22 07:50:04 puremessagevirtual postfix/qmgr[2351]: C8C6668AC8_1745F02F: removed
2013-04-22 07:50:02 puremessagevirtual milter[2001]: 51745F05_2001_2_1: pmx_spam: loading new data version 2013.4.21.213617
2013-04-22 07:50:04 puremessagevirtual milter[2001]: 51745F05_2001_2_1: accepted
2013-04-22 07:50:04 puremessagevirtual milter[2001]: 51745F05_2001_2_1: msg times: r=6.52s u=4.36s s=0.66s
2013-04-22 07:50:04 puremessagevirtual milter[2001]: 51745F05_2001_2_1: conn times: r=6.63s u=4.36s s=0.66s
2013-04-22 07:50:04 puremessagevirtual postfix/backend/smtpd[7199]: 534CF6B7AF_1745F0CB: client=localhost.localdomain[127.0.0.1]
2013-04-22 07:50:04 puremessagevirtual postfix/backend/cleanup[7201]: 534CF6B7AF_1745F0CB: message-id= 
2013-04-22 07:50:04 puremessagevirtual postfix/backend/qmgr[2481]: 534CF6B7AF_1745F0CB: from=, size=14177, nrcpt=1 (queue active)
2013-04-22 07:50:05 puremessagevirtual postfix/backend/smtp[7202]: 534CF6B7AF_1745F0CB: to=, relay=none, delay=0.98, delays=0.1/0.07/0.81/0, dsn=4.4.1, status=deferred (connect to btacsvr22.btac.nsw.edu.au[192.168.10.106]:25: Connection refused)