I have a zimbra installation that does not allow clear the queue of emails.
Try and from the graphical inferza zimbra and from the command line with / opt / zimbra / postfix / sbin / postsuper-d ALL defered but not delete the emails in the queue.
This is my version of Zimbra
Versión 7.1.3_GA_3346.FOSS 28 de Septiembre 2011
My linux version is
Linux ni01 2.6.32-39-server #86-Ubuntu SMP Mon Feb 13 23:15:11 UTC 2012 x86_64 GNU/Linux
I do not know who may be causing this, could you help me?