Enabling Websphere 6.0 security

Hi,
I am working on Websphere 6.0 ND server and I would like to provide secure access to Admin Console by enabling security. I tried enabling Global security and entering user credentials for Local OS user registry.then when i tried to start server, its state is always in starting mode. I would appreciate if you could let me know, if there is anything i am missing here... I got the error something like this..
       No received or invocation credential exist on the thread. The Role based authorization check will not have an accessId of the caller to check. The parameters are: access check method getName on resource Server and module Server. The stack trace is java.lang.Exception: dump thread stack for debugging at com.ibm.ws.security.role.RoleBasedAuthorizerImpl.checkAccess(RoleBasedAuthorizerImpl.java:354)
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thanks,
-rajStart Free Trial