Changes in 0.5.5
----------------

*  postfix: handle 'corrupt' queue
*  added sort by from/to/subject

Changes in 0.5.5.1
------------------

*  hotfix for a stupid typo that prevented postfix2 from working

Changes in 0.5.6
----------------

*  reverse sorting
*  much work on socket backend and the spfqueue frontend, now they
   are quite working
*  code cleanup
