Seyon 2.20b and above are released under the GNU General Public
License by kind permission of the author and original maintainer of
seyon, Muhammad M. Saggaf. I contacted him by snail mail to ask him to
open up the code and here is his response:

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I received your letter today (yes, I know it took a long time, it took a
trip half-way around the world and then back to my current address in the
U.S.). I share your view about license for Seyon, I think it is too
restrictive, especially that I'm not actively maintaining it. The purpose
behind that restriction was to prevent incompatible versions, really, but I
don't think it was the correct way of doing that. You have my permission to
modify the license (e.g. the GPL is just fine) and distribute the package
with the new license.

My very best wishes,

-- M. Saggaf
   msaggaf@erl.mit.edu

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    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA


See the file COPYING for full details of the GPL.

And here is the original license:

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  Seyon is Copyright (c) 1992 of Muhammad M. Saggaf. Seyon is not
  public domain. Permission is granted to use and distribute Seyon
  freely for any use and to sell it at any price without reference to
  the copyright owner provided that in all above cases Seyon is intact
  and is not made part of any program either in whole or in part and
  that this copyright notice is included with Seyon. Permission is
  also granted to modify the source as long as the modified source is
  not distributed without prior consent of the author.

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