Running two dsfw servers in our tree (edir 886), both OES2sp3 on

Everything was running fine up until a few days ago, now we seem to
have some weird dns issues.

If I do an nmblookup <mydomain> from either of my dsfw servers, they
both report back the IP address of our AS/400, instead of either of
their two IP addresses.

I'm thinking this is causing some of our dns issues.

Any suggestions?