A number of pieces of external code are included in the Exim distribution.
Regular expressions are supported in the main Exim program and in the Exim monitor using the freely-distributable PCRE library, copyright © 2001 University of Cambridge. The source is distributed in the directory src/pcre. However, this is a cut-down version of PCRE. If you want to use the PCRE library in other programs, you should obtain and install the full version from ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre.
Support for the cdb (Constant DataBase) lookup method is provided by code contributed by Nigel Metheringham of Planet Online Ltd. which contains the following statements:
Copyright © 1998 Nigel Metheringham, Planet Online Ltd
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 code implements Dan Bernstein's Constant DataBase (cdb) spec. Information, the spec and sample code for cdb can be obtained from http://www.pobox.com/~djb/cdb.html. This implementation borrows some code from Dan Bernstein's implementation (which has no license restrictions applied to it).
The implementation is completely contained within the code of Exim. It does not link against an external cdb library.
Support for Microsoft's Secure Password Authentication is provided by code contributed by Marc Prud'hommeaux. This includes code taken from the Samba project, which is released under the Gnu GPL.
The Exim Monitor program, which is an X-Window application, includes modified versions of the Athena StripChart and TextPop widgets. This code is copyright by DEC and MIT, and their permission notice appears below, in accordance with the conditions expressed therein.
Copyright 1987, 1988 by Digital Equipment Corporation, Maynard, Massachusetts,
and the Massachusetts Institute of Technology, Cambridge, Massachusetts.
All Rights Reserved
Permission to use, copy, modify, and distribute this software and its documentation for any purpose and without fee is hereby granted, provided that the above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in supporting documentation, and that the names of Digital or MIT not be used in advertising or publicity pertaining to distribution of the software without specific, written prior permission.
DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.