PLEASE NOTE:  (It seems I'm taking the same path Eggdrop did, but here goes...)

  One-way encryption is now implemented for those that support it (mIRC 5.41+)
older userfiles will not work without modification (just do /rChat.pass to every
user, and you'll be fine).  It simply uses the built-in identifier $hash ("should"
work on both 16-bit and 32-bit windows) in mIRC v5.41 up to recent versions.