Dear Friends,
At present I am more inclined towords using MAX812 as a supervisor for my P89V51RD2FA micros.
1. It has got Manual Reset provision which will usefull for FLASHMAGIC programming.
2. I will get a better supervisor better than P89V51RD2FA built in supervisor.
3. No watchdog feeding as in case of DS1232 I can turn off my ALE to reduce EMI.

If you guys have any further suggestion please post them I am desperately waiting for your replies, By tomorrow morning I am planning to place order for supervisors.

Thanks to all of your for your kind support.
Regards,
Prahlad Purohit