Today I updated a lotus connections 1.0.2 pilot to lotus connections 2.0. There's a great guide on the connections wiki site which covered all the basic topics.
Everything went fine, but the activities wont start anymore. Activity Service not available is the only message I get.
The Websphere Console says that the activities ear is up and running....
Edit 29.8.08:
Uninstalling the activities and re-installing solved the issue. It wors fine now.