Look at the NIS RPC protocol, enable IPv6 where possible, document where not. Try to find out what Solaris is doing. Try to find out what *BSD is doing. Introduce a version 3 binding file. Think about how to use libtirpc in glibc nss_nis module.
Update: client part is working, for RPMs and documentation see http://w3.suse.de/~kukuk/NIS-IPv6/
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