Forking and relicensing issues

[Ben Collins <bcollins@debian.org>]

Ok, I have a program that I intend to fork and start maintaing myself.
The Copyright file contains this information (program name changed to
protect the innocent):

--------------------------------------------------------------------
Redistribution and use in source and binary forms of Progfoo, with
or without modification, are permitted provided that the following
conditions are met:

1. Redistributions of source code must retain any existing copyright
   notice, and this entire permission notice in its entirety,
   including the disclaimer of warranties.

2. Redistributions in binary form must reproduce all prior and current
   copyright notices, this list of conditions, and the following
   disclaimer in the documentation and/or other materials provided
   with the distribution.

3. The name of any author may not be used to endorse or promote
   products derived from this software without their specific prior
   written permission.

ALTERNATIVELY, this product may be distributed under the terms of the
GNU General Public License, in which case the provisions of the GNU
GPL are required INSTEAD OF the above restrictions.  (This clause is
necessary due to a potential conflict between the GNU GPL and the
restrictions contained in a BSD-style copyright.)

THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
DAMAGE.
-------------------------------------------------------------------------

Now what I want to know is:

a) Can I just replace this file with the GPL (obviously the copyrights
in the files will remain intact and all work will be attributed to the
original authors)?

b) Better yet, can I replace it with the LGPL being as this is a
library?


NOTE: I am not subscribed to debian-legal, please Cc me in replies.

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Ben Collins <bcollins@debian.org>                        Debian GNU/Linux
OpenLDAP Dev - bcollins@openldap.org     The Choice of the GNU Generation
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