I have had a similar problem after rebuilding initrd. I had to do this to get my ATI HD3650 installed properly. Upon reboot, mount was complaining:
"mount: wrong fs type, bad option, bad superblock on /dev/mapper/VolGroup00-LogVol01,
missing codepage or helper program, or other error
In some cases useful info is found in syslog - try
dmesg | tail or so"
I did fsck to get the system to boot. Other volumes in the VolGroup00 (also ext4) are working fine now, but LogVol01 will not mount. dmesg | tail reports: "ext4: No journal on filesystem on dm-1"
Is there a way to rebuild the journal? It appears that the data on the drive is still okay.
Any Ideas? All the other forums that I checked did not give much help for this particular problem.