git clone 'https://github.com/u-u-h/cl-sendmail.git'
CL-Sendmail was written by Robert Marlow, as a rewrite of the sendmail.lisp code by Christophe Rhodes. Robert Marlow has not responded to my (and some other people's) patch requests, which is why this is a fork of the copy of version 0.5.5 from http://www.bobturf.org/software/cl-sendmail/
We depend (through cl-mime) on cl-qprint. Unfortunately, version 0.2.0 (still in quicklisp as of November 2013) is broken, and we therefore rely on the new maintained version of Max Rottenkolber available from http://mr.gy/maintenance/cl-qprint/ Note that the current git version there has a version number of 1.0.0-rc that asdf does not like. To ensure you are not using the broken cl-qprint I nevertheless added a versioned dependency in cl-sendmail.asd, and you will either have to edit the cl-qprint.asd file or cl-sendmail.asd, but at least it may force you to read this README.
In this fork we strive for improved portability. In particular, this version works with Allegro Common Lisp and needs no SBCL/CMUCL internals anymore.
Please check the original README file too.