What is needed is a system that 
records all patches, together with their current status (NEW, APPLIED, 
REJECTED (with reasons), and whatever other status), informs the submitter of 
any change, and does not allow for a patch merely to be forgotten.
  

It may be that Bugzilla could be coaxed into this role, although I suspect 
it's not particularly well adapted to this core task without some 
customisation.