After installing one can create provisioning groups that contain non-english letters like the norwegian æøå. The groups can be created, edited and deleted without any problems, untill you reboot.
After rebooting the groups appear empty even though the imports-X.xml files are still in the opennms folder, since the groups appear empty they cant be edited nor deleted. You can also not create any groups that contain the letters æøå after the reboot has taken place.
The nodes in the groups however still remain in the node list and function as normal.