I just upgraded to Jira 5.0.2 (from 5.0.1).
In the plugin manager, it says UPM needs an upgrade, but it does not upgrade.
It keeps saying: Preparing to update UPM... but never finishes.
I found this in catalina.out:
2012-04-03 16:22:33,821 QuartzWorker-1 ERROR ServiceRunner upmPluginUpgradeCheckJob [sal.jira.scheduling.JiraPluginSchedulerService] Unable to load a service descriptor for the job 'upmPluginUpgradeCheckJob'. This is usually the result of an obsolete service that can removed in the Administration section.