problem with sending from dynamic IP

[Michal Szymanski]

Hello,

I have a MailScanner/postfix/dovecot mail server at the office.
I have used thunderbird to read/send mail from my home PC by logging (TLS
authenticated) to the office mail server via dovecot. It worked perfectly
until I changed my ISP at home. Now I have a dynamic IP assigned (it was a
static, constant IP previously) and all emails sent from home get SPAM
status tags due to RCVD_IN_PBL and RCVD_IN_SORBS_DUL tests. 

Any hints how to fix that? I have googled the net but w/o success. ZEN
pages at spamhaus.net suggest turning on the authentication but it is
already turned on and it does not help.

regards,
Michal Szymanski

-- 
  Michal Szymanski (msz at astrouw dot edu dot pl)
  Warsaw University Observatory, Warszawa, POLAND