How to add keymapping by JavaAPI

Hi to all!

i want to add KeyMapping to one Record and use ModifyRecordsKeyMappingsCommand to do that

but after calling .execute() method .isCommandComplete() always return false.

There is my code:

KeyMapping km=KeyMappingFactory.createKeyMapping(new RemoteSystemId(10));
km.addKey(key);
.....
ModifyRecordsKeyMappingsCommand mrkm=new ModifyRecordsKeyMappingsCommand(mdmGate.getPool());
RecordKeyMapping rkm=KeyMappingFactory.createRecordKeyMapping(tbl,createRecCmd.getRecord().getId(),new KeyMapping[] {km});
mrkm.setKeyMappings(new RecordKeyMapping[] {rkm});
mrkm.setSession(mdmGate.getUserSessionId());
try {
        mrkm.execute();
} catch (CommandException ex) {
        ex.printStackTrace();
}
System.out.println(mrkm.isCommandComplete());

Does any one know what the problem is?

Thx in advance.