You cannot use DSCC to perform this task. Use the command line, as described in this procedure.
Configure replication compression on the replication agreement entry in the master server.
$ dsconf set-repl-agmt-prop -h host -p port suffix-DN \ consumer-host:consumer-port transport-compression:level
where level can be high, medium, low, or none.
For example, to use the fastest compression when sending replication updates to the consumer on host1:1389, type:
$ dsconf set-repl-agmt-prop -h host2 -p 1389 dc=example,dc=com host1:1389 \ transport-compression:high
For more information about setting the compression level, see Sun Java System Directory Server Enterprise Edition 6.2 Reference.