Stub class not found

Hi All,
I have RMI server and client program and both are running in my local machine. I'm using JDK1.6 for both program. Without stub class RMI server program is working nicely. But when I put my server program in another machine (different server) which is using JDK1.4 version and when I run my server program I got exception that is stub class (for my remote object class) is not found. So my question is that is it mandatory to create stub class for JDK1.4 version whereas in JDK1.6 I don't need to create stub class and server it's running. Please let me know if this is required to create stub class for JDK1.4 version and give a reference so that I can see also.

Thanks