Configuring a secondary NAB

Folks, Can some one give me an idea about how to configure a secondary nab and how to use it in authentication.

Here is what I’m trying to do : I need to build discussion forum. This will be accessible by the internal users and registered external users. Internal users will have their notes short name and pwd. External usesr will be registered in a new NAB. Both internal and external users will access the application through the same URL. I have an NAB for external users. I have built a custom login page and set it in DOMCFG. Now, how/where I will tell the server to use external nab for authentication.

What i want is, when the internal user enters his user name and pwd, we need to use names.nsf to validate, when an external user enters his user name and pwd, use the external nab

Is this clear?

Any help is much appreciated…

Subject: lookup directory assistance in admin help