public Context getInitialContext(Hashtable env) throws NamingException 
{
      // Get the login principal and credentials from the JNDI env
      Object credentials = env.get(Context.SECURITY_CREDENTIALS);
      Object principal = env.get(Context.SECURITY_PRINCIPAL);
      Principal securityPrincipal = null;
      /** Flag indicating if the SecurityAssociation existing at login should
      be restored on logout.
      */
      String flag = (String) env.get("jnp.multi-threaded");
      if (Boolean.valueOf(flag).booleanValue() == true)
      {
         /* Turn on the server mode which uses thread local storage for
            the principal information.
         */
         SecurityAssociationActions.setServer();
      }
      boolean restoreLoginIdentity = false;
      flag = (String) env.get("jnp.restoreLoginIdentity");
      if( flag != null )
         restoreLoginIdentity = Boolean.parseBoolean(flag);
      // See if the principal is a Principal or String
      if( principal instanceof Principal )
      {
         securityPrincipal = (Principal) principal; 
      }
      else
      {
         // Simply convert this to a name using toString
         String username = principal.toString();
         securityPrincipal = new SimplePrincipal(username);
      }
      // Associate this security context
      if( restoreLoginIdentity )
      {
         SecurityAssociationActions.setPrincipalInfo(securityPrincipal, credentials, null);
      }
      else
      {
         SecurityAssociationActions.setPrincipalInfo(securityPrincipal, credentials);
      }
      // Now return the context using the standard jnp naming context factory
      Context iniCtx = super.getInitialContext(env);
      if( restoreLoginIdentity )
      {
         // Use a proxy to pop the stack when the context is closed
         ClassLoader loader = SecurityAssociationActions.getContextClassLoader();
         ContextProxy handler = new ContextProxy(iniCtx);
         Class[] ifaces = {Context.class};
         iniCtx = (Context) Proxy.newProxyInstance(loader, ifaces, handler);
      }
      return iniCtx;
}

Take the env Context.SECURITY_PRINCIPAL and Context.SECURITY_CREDENTIALS and propagate these to the SecurityAssociation principal and credential. If Context.SECURITY_PRINCIPAL is a java.security.Principal then it is used as is, otherwise its treated as a name using toString and a SimplePrincipal is created. The Context.SECURITY_CREDENTIALS is passed as is.