The last release appears to have been fixpack 17, in 2015.
For a look at what it once was intended to be, see https://mediacenter.ibm.com/channel/WebSphere+Application+Server+V7+Feature+Pack+for+XML/33944932
(Note: This is not a plug. I haven't seen it in a decade, I have no idea what its current status is, for all I know it's unavailable or unsupported or broken or all the above. I'm just mentioning it so you know what I'm talking about when I compare my post-Xalan XML work with the Xalan codebase.)
-- ` /_ Joe Kesselman (he/him/his) -/ _) My Alexa skill for New Music/New Sounds fans: / https://www.amazon.com/dp/B09WJ3H657/Caveat: Opinionated old geezer with overcompensated writer's block. May be redundant, verbose, prolix, sesquipedalian, didactic, officious, or redundant. Feel free to call him on it.
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Description: OpenPGP public key
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Description: OpenPGP digital signature