Sieh mal in der Admin Hilfe nach. Dort steht im Index unter Language Packs}upgarding:
Before you upgrade a Domino server, be aware of the following issues:
If you have a Domino server with language packs installed, do not upgrade that server until the updated language packs for the latest Lotus Domino release are available. When you upgrade a Domino server with language packs installed, the upgrade process replaces all translated templates with English language templates.
D.h. Nach dem Upgrade musst Du das LP wieder einspielen (Replace).
Andreas