Blank data Logical volume, after Mainboard+System update

[toml01a]

hello
After changing mainboard from à Xeon(32) to an opteron(64),
i have reinstalled a 64Bits Linux (Scientific 5.3) à Red HAT clone
i have unplugged data disk during installation
when System is up, Data Logicalvolumes are blank

i have reused the same PCI controller(promise) managing theses disks
i have tesed disk to another controller, same problem

after installation
VG and LV are imported by the system, all LVM structure are OK
but.. Filesystem originally ext3 are changed for unknown reason to ext2 ? (journal lost ?)
other problem, when mounting "read-only" file systems are blank (only lost+found)

to verify if the disk is really blank, i have tryed this
od -ax /dev/vg.../... | strings | more
i can see/recognise some datas and scripts stored on Logical volume.

somebody have an idea ?

[toml01a]

i have found the problem !
After installation, i have installed our specific tracing tools, that was a good idea to to this before lunch! (it send root log command to a "mirador" server)

the mirador and doors show:
a bad admin user have formated the volumes width a simple mkfs /dev/.... and logout, the clear word = "sabotage"

there is a tips to recover data on a ext3 File system formated
width mke2fs /dev/... ?