If you really want to run your own whois server for your IP allocations, RIPE WHOIS Server is the first that comes to mind:
http://www.ripe.net/ripencc/pub-services/db/ or http://freshmeat.net/projects/ripewhois/ I believe this is the NSI version you were referring to: http://www.nw.com/nw/WWW/software/whois.html These are the only two that I personally know about. > Perhaps I am being misunderstood (or perhaps I'm just completely > stupid)... We are looking to serve authoritative whois records. We > will also be using our rwhois server for our IP blocks which will be > fully redelegated from ARIN (today they are simply reassigned, and ARIN > maintains the records).