Specifying CLREPL in the ServerTasks line of the Domino server ini file will take precedence over the CLUSTER_REPLICATORS setting in controlling how many cluster replication threads are started by the server. 

Note that in earlier versions of Domio the only method of starting multiple cluster repication threads was to list CLREPL multiple times in ServerTasks.  This has been replaced by the more streamlined use of the CLUSTER_REPLICATORS parameter, and using both at the same time may lead to unexpected behavior.

Example: A Domino server which is a member of a Domino cluster has CLREPL listed in the ServerTasks line, and CLUSTER_REPLICATORS=3 as a seperate ini entry.  When this Domino server starts, one cluster replication thread is started rather than three due to the CLREPL entry taking precedence.

Recommendation: For R6 and later servers, remove all references of CLREPL from ServerTasks and instead use CLUSTER_REPLICATORS parameter to control the number of cluster threads used by the server.