There is a nasty inconsistency - the original RedHat 5.2 included bind-8.1.2-5, that was enabled in runlevels 3,4 and 5 by default (in included /etc/rc.d/rc{2,3,4}.d/S55named symlinks). But the errata release of bind - binf-8.2.2_P3-0.5.2 does not have the daemon enabled by default (it includes /etc/rc.d/rc{0,1,2,3,4,5,6}.d/K45named symlinks). As a result, upgrading to the errata bind suddenly disables bind and even running chkconfig does not fix it (since /etc/rc.d/init.d/named does not specify runlevels).
This is because the package was originally built for 6.1 (where bind=off is the default), and the people doing the 5.x backport overlooked it. It'll be fixed if there will be another problem with bind, but this in itself doesn't become a new update. For now, change the line # chkconfig: - 55 45 in /etc/rc.d/init.d/named to # chkconfig: 345 55 45