DNS Parser

Since IP allocations have been such a hot topic lately, I thought I'd ask this -- Does anyone know of a simple script that will go through a list of BIND primary files, or more and output a list of output like this: secondlevel.domain --> address thirdlevel.secondlevel.domain --> address and so on for several thousand domain files. We acquired a company that never kept their reverses up to date and need a simple way of building them to keep track of their IP utilizations. There is probably one written in perl out there somewhere, I'd appreciate a pointer. Thanks, Deepak Jain AiNET