The jfs0508 file contains the latest JFS.IFS/JFS.SYM , UJFS.DLL/UJFS.SYM,
CLRBBLKS.EXE/CLRBBLKS.SYM,JFSCHK32.EXE, the JFS.TDF and the TRC012F.TFF file.
.
Please unzip this file in the root directory after you have made a
backup of the following files.
.
\OS2\JFS.IFS
\OS2\JFS.SYM ( IF PRESENT )
\OS2\DLL\UJFS.DLL
\OS2\DLL\UJFS.SYM ( IF PRESENT )
\OS2\CLRBBLKS.EXE
\OS2\CLRBBLKS.SYM ( IF PRESENT )
\OS2\JFSCHK32.EXE
\OS2\SYSTEM\TRACE\JFS.TDF
\OS2\SYSTEM\TRACE\TRC012F.TFF
.
The modules contain some important fixes added on top of jfs0328
.
Fixes in JFS.IFS
.
Xcopy hang when transferring more than 45GB of data.
Xcopy hang when booted from floppy / cdrom.
.
Some fixes that have gone into UJFS.DLL and CLRBBLKS.EXE
.
Trap during chkdsk if running dir on the same drive from client.


from jfs0328 readme:
Fixes in JFS.IFS:

Trap when swapper file is on JFS volume.
Hang when swapper file on JFS volume is being truncated.
Hang with heavy file I/O on JFS volume 

Fixes that have gone into UJFS.DLL:

Cyrillic character files being moved into the lost+found directory.
Chkdsk takes a long time to complete Phase0 ( logredo ).