Just found this on redhat regarding a recent subject on the list:

(http://www.redhat.com/support/wpapers/redhat/ext3/#advantages)

The */tune2fs/* program can add a journal to an existing ext2 file 
system. If the file system is already mounted while it is being 
transitioned, the journal will be visible as the file *.journal* in the 
*root* directory of the file system. If the file system is not mounted, 
the journal will be hidden and will not appear in the file system. Just 
run *tune2fs -j /dev/hda1* (or whatever device holds the file system you 
are transitioning) and change *ext2* to *ext3* on the matching lines in 
*/etc/fstab*.

Rick Herrem