Ever since upgrading to JIRA 5.1 I am getting the following in the logs.

2012-07-23 14:53:00,850 QuartzWorker-0 ERROR ServiceRunner Service Provider Token Remover [sal.jira.scheduling.JiraPluginSchedulerService] Unable to load a service descriptor for the job 'Service Provider Token Remover'. This is usually the result of an obsolete service that can be removed in the Administration section.

This is happening because the Atlassian OAuth plugin has renamed its token deleting job from 'Service Provider Token Remover' to 'Service Provider Session Remover'. JIRA should not log an ERROR message for this, it's just part of normal operation.

The error in the logs does not adversely affect the normal operation of JIRA in any way.