LOG: incomplete startup packet

What is the cause of this line in the LOG?
What could be done in order to fix it?

[2006-01-16 20:00:10 BRT]  LOG:  autovacuum: processing database "cep"
[2006-01-16 20:01:17 BRT]  LOG:  autovacuum: processing database "postgres"
[2006-01-16 20:02:03 BRT] [unknown] LOG:  incomplete startup packet
[2006-01-16 20:02:18 BRT]  LOG:  autovacuum: processing database "sentinela"
[2006-01-16 20:03:20 BRT]  LOG:  autovacuum: processing database "template1"
[2006-01-16 20:04:20 BRT]  LOG:  autovacuum: processing database "detran"

2006-01-17 10:13:00 LOG:  pacote de inicialização incompleto
2006-01-17 10:16:00 LOG:  pacote de inicialização incompleto
2006-01-17 10:19:02 LOG:  pacote de inicialização incompleto
2006-01-17 10:22:03 LOG:  pacote de inicialização incompleto
2006-01-17 10:22:03 LOG:  arquivo do log de transação "0000000700000064" reciclado

Regards,

Rodrigo Hjort
GTI - Projeto PostgreSQL
CELEPAR - Cia de Informática do Paraná
http://www.pr.gov.br