I used Linuxconf to change the NIS domain on a machine. I then rebooted the machine. The machine correctly picks up the new domainname which is set properly in /etc/sysconfig/network. However, /etc/yp.conf still lists the old domain and so the machine is trying to broadcast for a NIS server for the old domain.
This appears to be working in linuxconf-1.17r2 from Raw Hide. Please reopen this bug if you find that this is not the case on your system.