In RHQ we ran into a problem defaulting to the local time zone. See https://bugzilla.redhat.com/show_bug.cgi?id=1161806 for details. The task scheduling service consequently configures Joda Time to default to UTC. This is a global setting which means that any DateTime object created will have its time zone set to UTC by default. There was some concern raised that this could have adverse side effects for other Joda Time clients running in the same JVM. This is being discussed on the hawkular-dev mailing list. I pushed changes for using UTC without making it a global default to https://github.com/jsanda/hawkular-metrics/commit/dbea29a29de90a5ceaff45cbdd32c5e5c24c7193 if we decide that is the way to go. This ticket will be updated with any action items that come out of the mailing list discussion.