Spamassasin works, but spamc does not

If I use [SpamAssassin client program] = spamassassin (Standalone program),
everything works and mail is checked for spam.
If I switch to [SpamAssassin client program] = spamc (Client for SpamAssassin filter server spamd)
it’s stop checking mail for spam.
MTA agent is Postfix.
Examining /var/log/mail.log I see following error:
spamd: unauthorized connection from 123.123.123.123 [123.123.123.123]:47382 to port 783, fd 5 at /usr/sbin/spamd line 1627.
where 123.123.123.123 is my public ip.
# netstat -natpu
shows
tcp 0 0 127.0.0.1:783 0.0.0.0:* LISTEN 13027/perl

Why connection is coming from my public ip rather then the localhost?
Any suggestions?