Authentication Exception

[Bala Subramanian]

Hi
I am trying to access the JMX Mbeans and their attributes.I have installed weblogic
6.1 sp2 on windows 2000 server .Am getting the Mbeans attributes and values.It is
working fine.
I have installed weblogic 6.1 sp1 on windows 2000 server and tried to access their
mbeans attributes and values,am getting error.

java.lang.ClassCastException: weblogic.security.acl.DefaultUserInfoImpl
at weblogic.kernel.BootServicesImpl.authenticate(BootServicesImpl.java:189)
at weblogic.kernel.BootServicesImpl.invoke(BootServicesImpl.java:145)
at weblogic.rjvm.RJVMImpl.dispatchRequest(RJVMImpl.java:620)
at weblogic.rjvm.RJVMImpl.dispatch(RJVMImpl.java:581)
at weblogic.rjvm.ConnectionManagerServer.handleRJVM(ConnectionManagerServer.java:164)
at weblogic.rjvm.ConnectionManager.dispatch(ConnectionManager.java:640)
at weblogic.rjvm.t3.T3JVMConnection.dispatch(T3JVMConnection.java:454)
at weblogic.socket.NTSocketMuxer.processSockets(NTSocketMuxer.java:643)
at weblogic.socket.SocketReaderRequest.execute(SocketReaderRequest.java:24)
at weblogic.kernel.ExecuteThread.execute(ExecuteThread.java:139)
at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:120)
End server side stack trace

Any one of you could give me some tips on the above mentioned problems asap.....

Regards
Bala