Problem with Syncrepl

[Barrow H Kwan <bhkwan@thoughtworks.com>]

I am running Openldap-2.3.4 with BDB-4.3.28 and having problem with 
Syncrepl.  Changes on the master ( producer ) sometimes didn't get to the 
slave ( consumer ).  Sometimes the slave ( consumer )'s server has some of 
the data gone to nowhere.  ( eg  a user was created on the master for a 
long time.  When the slave start running the first time for a few hours, 
that user will disappear from the slave all of a suddenly.  This is very 
random.  Sometimes, it is user ABC, sometimes it is user DEF, etc.. )

here is the partial configuration on my master and slave server

any help will be appreciated.

thanks

master:
....
lastmod on
sizelimit 100000
timelimit 36000
overlay syncprov
syncprov-checkpoint 100 10
syncprov-sessionlog 100
....

slave A:
....
access to dn.sub="dc=Corporate,dc=ThoughtWorks,dc=COM"
        by dn="uid=slave01,ou=IS,dc=Corporate,dc=EXAMPLE,dc=COM" write
        by * read
lastmod on
sizelimit 100000
timelimit 36000
syncrepl rid=005
        provider=ldap://ldap.example.com:389
        type=refreshOnly
        interval=00:00:01:00
        searchbase="dc=Corporate,dc=EXAMPLE,dc=COM"
        scope=sub
        attrs="*,+"
        filter="(objectClass=*)"
        updatedn="uid=slave01,ou=IS,dc=Corporate,dc=EXAMPLE,dc=COM"
        bindmethod=simple
        binddn="uid=slave01,ou=IS,dc=Corporate,dc=EXAMPLE,dc=COM"
        credentials=secret
....


slave B:
...
access to dn.sub="dc=Corporate,dc=ThoughtWorks,dc=COM"
        by dn="uid=slave02,ou=IS,dc=Corporate,dc=EXAMPLE,dc=COM" write
        by * read
lastmod on
sizelimit 100000
timelimit 36000
syncrepl rid=124
        provider=ldap://ldap.example.com:389
        type=refreshOnly
        interval=00:00:01:00
        searchbase="dc=Corporate,dc=EXAMPLE,dc=COM"
        scope=sub
        attrs="*,+"
        filter="(objectClass=*)"
        updatedn="uid=slave02,ou=IS,dc=Corporate,dc=EXAMPLE,dc=COM"
        bindmethod=simple
        binddn="uid=slave02,ou=IS,dc=Corporate,dc=EXAMPLE,dc=COM"
        credentials=secret
,..