[bxhsix]

hello, in the beginning I used java as client and C++ as server and they worked well. But when I made an operation idempotent in the ice file, the problem arised. Whenever the client calls the idempotent operation of the server, the server will throw exception as follows:
...warning: dispatch exception: Object.cpp:292: Ice::MarshalException:
protocol error: error during marshaling or unmarshaling:
unexpected operation mode. expected = ::Ice::Idempotent received = ::Ice::Normal
...
If I remove the keyword idempotent in the ice file and re-slice2cpp, the server works well again. What's the problem?
Thanks a lot!