(I am sys admin!)

I can receive email, but when I try to send an email from my home office via our work email server I get the following reply:

Your message did not reach some or all of the intended recipients.

  Subject:    Test
  Sent:   19/08/2014 17:02

The following recipient(s) cannot be reached:

'Joe Blogs' on 19/08/2014 17:02 Server error: '554 5.7.1 Service unavailable; Client host [my-ip-here] blocked using zen.spamhaus.org; http://www.spamhaus.org/query/bl?ip=my-ip-here'

I went to that URL and it says the following:

Ref: PBL231588

81.152.0.0/13 is listed on the Policy Block List (PBL)

Outbound Email Policy of BT Retail for this IP range:

It is the policy of BT Retail that unauthenticated email sent from this IP address should be sent out only via the designated outbound mail server allocated to BT Retail customers. Please consult the following URL for details on how to configure your email client appropriately. http://btybb.custhelp.com/cgi-bin/btybb.cfg/php/enduser/cci/bty_adp.php?p_sid=fPnV4zhj&p_faqid=6876

Removal Procedure

Removal of IP addresses within this range from the PBL is not allowed by the netblock owner's policy.

Going to this URL just says:

This site has been disabled for the time being.

Does anyone know what I should do to allow me to send emails from my home ip - the site suggests I can configure my email client? (note that I have configured the client to use smtp authentication)