Java APIs

hi!

I have a simple RMI app that writes something on a text file (client) and prints the file content (server). During execution, it gives this error:

Exception in thread "main" java.lang.UnsupportedClassVersionError: server/ServerImpl (Unsupported major.minor version 49.0)

i following these steps from http://engronline.ee.memphis.edu/advjava/misc/rmi2.htm:

File Directory: C:\RMISample\*.java
Class Directory: C:\RMISample\server\*.class, C:\RMISample\client\*.class

1. Place interface class, which extends Remote on the client and server.
2. Place class extending RemoteObject on server.
3. Generate stubs and skeleton by running rmic. Copy the stubs to the client.
4. Start the registry on server.
5. Start program that creates and registers objects on the server.
6 Run program that looks up server objects and invokes remote methods.

I'm not sure how to do steps 5 and 6, though (i did java server.ServerImpl)

thanks in advance...