[galaxy-dev] 'Never ending' jobs in history

Hi, Occasionally, we see jobs that are constantly in the 'job running' state in the history. This is despite the fact that the job completed correctly. I can also see in the paster.log file that Galaxy has picked up on the fact that the job ended, but it just hasn't updated the UI. Clicking the eye for the 'running' history items does show the results of the run. This does not happen all the time. Is this a known issue and/or how can I resolve it? Thanks, Chris