Command execution problems: org.hibernate.MappingException: Named query not known

While executing e.g. a FindProcessInstanceByIdCmd or FindProcessInstanceByKeyCmd it occured a org.hibernate.MappingException: Named query not known: findProcessDefinitionsById or org.hibernate.MappingException: Named query not known: findProcessDefinitionsByKey respectivly.

FindProcessInstanceByIdCmd and FindProcessInstanceByKeyCmd are the known commands with this problem. Maybe other commands are effected too.