Sprint 4 bug fixes (rebased onto develop)



This is the same as gh-313 but rebased onto develop.

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Includes the fix for:
http://lists.openmicroscopy.org.uk/pipermail/ome-users/2012-December/003484.html

I'd like to add a few more ticket fixes before this gets merged, but wanted to open it now so that I could respond to the ome-users thread.