Is it possible that recovering a disk with jffs2 file system ?

Is it possible that recovering a disk with jffs2 file system ?

DataClinic.com specializes in data recovery on flash drives. You might try them.
FWIW - flash has a problem in that after a number of writes, data blocks suffer wear.
There comes a point where data retrieval fails. There isn't a builtin way to resurrect a dead jffs2 filesystem, as far as I know.