Comment 1 for bug 67112

Downloaded the source code. The msgid is here

### code ####
def run_synaptic(self, id, action, lock):
    try:
      apt_pkg.PkgSystemUnLock()
    except SystemError:
      pass
    cmd = ["gksu", "--desktop", "/usr/share/applications/update-manager.desktop",
           "--", "/usr/sbin/synaptic", "--hide-main-window",
           "--non-interactive", "--parent-window-id", "%s" % (id) ]
    if action == INSTALL:
      cmd.append("--progress-str")
      cmd.append("%s" % _("Please wait, this can take some time."))
      cmd.append("--finish-str")
      cmd.append("%s" % _("Update is complete"))
      f = tempfile.NamedTemporaryFile()
      for pkg in self.cache:
          if pkg.markedInstall or pkg.markedUpgrade:
              f.write("%s\tinstall\n" % pkg.name)
      cmd.append("--set-selections-file")
      cmd.append("%s" % f.name)
      f.flush()
      subprocess.call(cmd)
      f.close()
    elif action == UPDATE
   ...
### end code ###

So, the issue is here or in synaptic itself.

BTW, I'm not sure, but the "Update is complete" message is never used.