there was an optimization placed in JDK 1.4: RFE 4308161

     here is a typical call sequence:

         A (no principals)
         B (no principals) -> Subject.doAs(S, C)
         C (as S) -> security check

     and the domains passed to the policy implementation would be:

         A (no principals)
         B (no principals)
         C (as S)

     however, if the customer's call sequence is something like:

         A (no principals)
         B (no principals) -> Subject.doAs(S, A)
         A (as S) -> security check

     then because of the optimization performed in the above RFE,
     the only domains passed to the policy implementation will be:

         A (no principals)
         B (no principals)

the above behavior is causing problems with developers
who want access to the domains that are optimized away.
the optimization for the above RFE should be removed.