rsh is malfunctioning due to pf

Hello people.
I have ipcad installed on 2 PC's running 5.3-RELEASE and 5-STABLE from
Nov 21. ipcad (ports/net-mgmt/ipcad) provides ability to control them
by rsh (ipcad implement rsh server by yourself). While using pf with
primitive rulesets rsh stops its working. It seems like pf drop short
packets.

Using tcpdump -n -e -ttt -i pflog0 I see:
...
294896 rule 1/3(short): pass out on lo0: IP 127.0.0.1.514 > 127.0.0.1.680: FP 0:387(387) ack 18 win 35840 <nop,nop,timestamp[|tcp]>
...

Some parts from pfctl -sa output
FILTER RULES:
pass in quick all
pass out quick all

...
Counters
  match                               1319            8.1/s
  bad-offset                             0            0.0/s
  fragment                               0            0.0/s
  short                                192            1.2/s
  normalize                              0            0.0/s
  memory                                 0            0.0/s
...

-- 
Andrew Degtiariov 
DA-RIPE