test more: init.d script - stop, start and error conditions

test three synchronized instances

dgrey as a spamassassin plugin?
 - will not work unless we can return 450 (or some other code)

documentation:
  fix XXXs. document whitelist_recipients & whitelist_senders file format.
  document the scripts in etc/
  make note that servers should be synchronized time wise!
  crypt is limited to 8 characters! make note of this in docs! also update config file!
  theory of operation/inner workings
  database components
    file list
  coding policies
    die should not need to be called anywhere (except if protected by eval{})
    use $mux methods rather than doing I/O on wrapped fhs directly

create debian package

remote-ping / ping-all command?

allow specification of own host address in poll hosts?
  what if we have set up a poll connection to ourselves?
  this way one could use the same configuration file
  across many hosts

stronger crypto

rewrite in C

write node id in each poll message, allowing arbitrary communication graphs

improve installation, allow overwrite of perl sitelib and perl shebang with --arguments
