ABAP Proxy Problem

I write a sender abap proxy in our R/3 system, client 200(which is our develop client), it works well.

But when I switch to Client 300(which is our test client), it throws out a exception

CX_AI_SYSTEM_FAULT during running.

The termination occurred in the ABAP program "CL_PROXY_FRAMEWORK============CP"

in "XI_PROCESS_CALL_XMB".

The main program was "ZRPO_DATALOAD ".

The termination occurred in line 40 of the source code of the (Include)

program "CL_PROXY_FRAMEWORK============CM00Z"

of the source code of program "CL_PROXY_FRAMEWORK============CM00Z" (when

calling the editor 400).

I've checked the sxi_monitor of R/3, no xml message there.

Anyone knows why?