http://en.ecomstation.ru/projects/jrescuer/
"If you are having trouble getting to your data on your JFS partition you can try and recover/undelete your data with JRescuer. If you encounter the rare problem that during a CHKDSK your machine keeps hanging there you can "unlock" the JFS partition with JRescuer. In case of an emergency you can also recover data from a JFS volume even if you don't have JFS.IFS loaded (the file system driver).
JRescuer includes:
* JRescuer (TM) -- recover utility (VIO)
* JUne (TM) -- undelete utility (PM)
* ISJ -- shows info about SuperBlock and allows change chkdsk state (VIO). "
Source: OS2.jp