It seems that file ip4addr.h is missing in both pre1 and pre2 distributions: [ ~/src/rbldnsd-0.74pre1]$ make cc -O -DVERSION='"0.74pre1 2003-03-29"' -c rbldnsd.c In file included from rbldnsd.c:23: rbldnsd.h:2: ip4addr.h: No such file or directory *** Error code 1 [ ~/src/rbldnsd-0.74pre2]$ make make: don't know how to make ip4addr.h. Stop -- Dmitry Agaphonov