replication is not working due "Unable to parse the response"

[Fosiul Alam]

HI
I am trying Initialise consumer and i am seeing this in the master server :

Unable to parse the response to the startReplication extended
operation. Replication is aborting.
Incremental update failed and requires administrator action
 NSMMReplicationPlugin - Beginning total update of replica "agmt="cn=" (:636)".
 NSMMReplicationPlugin - Finished total update of replica "agmt="cn="
(:636)". Sent 253 entries.
 NSMMReplicationPlugin - agmt="cn=" (:636): Unable to parse the
response to the startReplication extended operation. Replication is
aborting.
 NSMMReplicationPlugin - agmt="cn=" (:636): Incremental update failed
and requires administrator action

in slave :

NSMMReplicationPlugin - repl_set_mtn_referrals: could not set
referrals for replica dc=xxx,dc=lan: 32
NSMMReplicationPlugin - multimaster_be_state_change: replica
dc=xxx,dc=xxx is going offline; disabling replication

what could be the issue??
how to solve this issue??

Thanks