LDAP in 8.0.3

We had LDAP working fine in our 8.0.3 production environment (AIX) for several months, and then started getting intermittent 503 errors (Server temporarily unavailable). If you try again, there is no error. This can happen when logging in or when accessing a screen. Lawson looked at it and recommended some performance changes. We implemented them all except for moving to ESP6. Our log shows that LDAP has either “timed out” or is “waiting for time out”. We are getting these even with little load on the system (Sunday at 4 AM). We put this on our test box and it works fine, even under a load. We had two consultants look at this and tune our system, but we are still getting the errors. Any help would be greatly appreciated! Thanks - Chris