On an updated machine, mount fail heavily. The "mount" output show the correct behaviour, but "df" displays for any mount point (/proc and /dev/pts too) same space info. "ls" show empy file systems other than "/". I have /var and /var/spool/squid (remember?) on separated file systems, and on fstab I DON'T use disk labels, but partitions devices.
My apologizes... Standard disclaimer on "not enough caffeine" be applied. Apparently something/someone changed to 644 directories and files permissions on /etc and /etc/rc.d, and conseguently things like /etc/rc.d/rc.sysinit can't run at boot. "df" problem is consequence of reading older /etc/mtab, as example.
Ok, resolving to NOTENOUGHCAFFEINE... Oops, that state is missing in Bugzilla. ;) Feel free to report this bug. ;)