Fails to process lines matching "disconnect from unknown[unknown]"

[Justin Lloyd]

Running pflogsumm 1.1.5-1 on Ubuntu 16.04 against log messages from yesterday throws the following messages:

Use of uninitialized value $domain in string eq at /usr/sbin/pflogsumm line 1546, <> line 131435.
Use of uninitialized value $domain in substitution (s///) at /usr/sbin/pflogsumm line 1552, <> line 131435.
Use of uninitialized value $hostID in hash element at /usr/sbin/pflogsumm line 773, <> line 131435.
Use of uninitialized value $hostID in hash element at /usr/sbin/pflogsumm line 774, <> line 131435.
Use of uninitialized value $hostID in hash element at /usr/sbin/pflogsumm line 775, <> line 131435.
Use of uninitialized value $hostID in hash element at /usr/sbin/pflogsumm line 777, <> line 131435.
Use of uninitialized value $hostID in hash element at /usr/sbin/pflogsumm line 779, <> line 131435.
Use of uninitialized value $hostID in hash element at /usr/sbin/pflogsumm line 778, <> line 131435.

Line 131435 from our mail.log is

Oct 18 02:24:03 hostname postfix/smtpd[22574]: disconnect from unknown[unknown] helo=1 mail=1 rcpt=1 data=1 rset=1 commands=5

and there is only one other similar line in the file. This is the first time I've seen this error in the year that I've been using the script.