11.1.1.5 OID - Intermittent disconnects from database

Hello, we're using OID 11.1.1.5 connecting to a 11.2.0.3 database as its repository. Everything works, but we're intermittently encountering errors in the oidmon and oidldap logs such as ORA-03113: end-of-file on communication channel and we experience errors using ODSM and any LDAP calls we're making at the time. It recovers, but there's an interruption in the services. We have a firewall between the boxes, but the admin says he can't see any blocked traffic. The idle timeout on the firewall is two hours, and we have our sqlnet.expire_time set to 3 (minutes) which should keep it from ever timing out