Remove old definition of MD5-DIGEST.

scheme/lib/pop3.scm

@@ -259,13 +259,6 @@
     (pop3-log connection (format #f "<- ~a" command))
     (pop3-handle-response (pop3-read-response connection) command)))
 
-
-;; who will write this in Scheme?
-(define (md5-digest str)
-  (car (run/strings (md5sum) (<< ,str))))
-; the name of the program differs among the distributions
-; e.g. in FreeBSD it is called md5
-
 (define (pop3-dump fd)
   (let loop ((line (read-crlf-line fd)))
        (cond ((and (not (eof-object? line))