Djava.rmi.server.codebase=file:/opt/jbuilder4/samples/RMI/classes/ -Djava.security.policy=file:/opt/jbuilder4/samples/RMI/SimpleRMI.policy 
设置不对(现在是缺省的)
如果是windows的话 如file:d:\javafile\RMI\classes\
设置成你机器的实际情况
祝你成功!