The JFS developer forwarded to me the "latest and greatest" JFS-related fixes. This will substantially reduce JFS fragmentation and increase stability under load (among other fixes). Get
ftp://testcase.boulder.ibm.com/ps/fromibm/os2/jfs0622.zip
This will expire in a few days. I think there are those who keep an archive of the stuff that appears on testcase.
-scott
Source: OS2VOICE