When I set the trash folder for a gmail account to the Gmail/Trash folder, trying to delete emails hangs, akonadi has to be fsck'd and restarted. For gmail accounts, it should probably not try to move the messages to trash since gmail will put them there automatically.
I'm not sure anymore if this is a bug or a manifestation of the gmail bug here: https://bugs.kde.org/show_bug.cgi?id=338658 so closing this for now. *** This bug has been marked as a duplicate of bug 338658 ***
This bug has had its resolution changed, but accidentally has been left in NEEDSINFO status. I am thus closing this bug and setting the status as RESOLVED to reflect the resolution change.