I needed mmencode but didn't have it. Clojure nubware over Apache Geronimo to encode plain text as quoted-printable.

quoted_printable.clj

(ns workstationClojure.quoted-printable
  (:require [clojure.java.io :as jio])  
  (:import [java.io ByteArrayOutputStream ByteArrayInputStream]
           [org.apache.geronimo.mail.util QuotedPrintableEncoder]))

;; http://geronimo.apache.org/maven/specs/geronimo-javamail_1.4_spec/1.6/apidocs/org/apache/geronimo/mail/util/QuotedPrintableEncoder.html
;; In project.clj,
;;    [geronimo/geronimo-mail "1.1"]

;; Geronimo's API is asymmetric, and in somewhat weasily ways, so we
;; need two differently shaped driver loops. In particular,
;; QuotedPrintableEncoder.decode(buffer, offset, len, out)
;; requires the entire message to be in buffer, which defeats
;; the streaminess of these guys.

(defn qp-streams! [instream outstream]
  (let [buffer (byte-array 1024)
        encoder (QuotedPrintableEncoder.)]
    (loop [bytes-read (. instream read buffer)
           bytes-wrote 0]
      (if (= -1 bytes-read)
        (inc bytes-wrote)
        (do
          (. encoder encode buffer 0 bytes-read outstream)
          (recur (. instream read buffer) (+ bytes-read bytes-wrote)))))))

(defn unqp-streams! [instream outstream]
  (let [decoder (QuotedPrintableEncoder.)]
    (loop [byte-decoded (decoder instream)
           bytes-wrote 0]
      (if (= -1 byte-decoded)
        bytes-wrote
        (do
          (outstream write byte-decoded)
          (recur (decoder instream) (inc bytes-wrote)))))))

(defn- shovel-bytes-from-string [ ^String instring ^String encoding processor!]
  (let [inbytes (ByteArrayInputStream. (. instring getBytes))
        outbytes (ByteArrayOutputStream.)]
    (processor! inbytes outbytes)
    (. outbytes toString encoding)))

(defn- shovel-files [infile outfile processor!]
  (with-open [ins (jio/input-stream infile)]
    (with-open [outs (jio/output-stream outfile )]
      (processor! ins outs))))

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;


(defn qp-files! [infile outfile]
  (shovel-files infile outfile qp-streams!))

(defn unqp-files! [infile outfile]
  (shovel-files infile outfile unqp-streams!))

(defn qp [instring]
  (shovel-bytes-from-string instring "US-ASCII" qp-streams!))

(defn unqp [instring & encoding]
  (shovel-bytes-from-string instring encoding unqp-streams!))