ProgramCall "on thread" slower than "off thread"?

Hi.

I am trying to get some numbers on the speed of various parts of the "java->as/400 interaction" stuff we are building.

Right now I am looking at the ProgramCall while calling the API I believe should be the quickest to actually do serverside (converting the *CURRENT date to *DTS format) and I have found that the native approach is the SLOWEST. Is this right? Host is V5R3.

PC->AS/400
==========
stay on thread = false
is thread safe = true
0.9956 ms/call

AS/400->AS/400 not native
=======================
stay on thread = false is thread safe = true 1.2036 ms/call

AS/400->AS/400 native jt400 on system
=================================
stay on thread = true is thread safe = true 2.3937 ms/call
The code in question looks like (not runnable):
=================
AS400 as400 = new AS400();
as400.connectService(AS400.COMMAND);
String program = "QWCCVTDT.PGM";
AS400DataType[] signature = { new AS400Text(10), new AS400Text(1), new AS400Text(10), new AS400Text(8), new AS400Text(100) };

AS400Function f = new AS400Function(as400, program, signature);
ProgramCall programCall = f.getProgramCall();
programCall.setThreadSafe(true);
System.out.println(as400);
System.out.println("stay on thread = " + programCall.isStayOnThread());
System.out.println("is thread safe = " + programCall.isThreadSafe());
int count = 10000;
long start = System.currentTimeMillis();
for (int j = 0; j < count; j++) {
String[] result = f.call(new String[] { "*CURRENT", "", "*DTS" });
}
System.out.println((System.currentTimeMillis() - start) * 1.0 / count + " ms/call");

=================

I'd like to hear opinions and experiences :)