This jar file provides a patch mechanism that you run against a local copy of your pubnamesmod.ntf (which you created using File - Database - New Copy from pubnames.ntf).
Copy the jar into [Notes]/jvm/lib/ext and start it with the Notes jvm java -jar LDAPFixForDomino.jar.
More details what it does are here:
Stephan is the developers, Niklas only committer.