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diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index d16f2b1f6b6..68ce460fb27 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,9 @@
+2003-05-08  Dave Love  <fx@gnu.org>
+
+        * international/utf-7.el: New file.
+
+        * international/mule-conf.el (utf-7): New.
+
 2003-05-06  Kenichi Handa  <handa@m17n.org>
 
         * international/mule-conf.el (utf-16-be) 
diff --git a/lisp/international/utf-7.el b/lisp/international/utf-7.el
new file mode 100644
index 00000000000..f45c7cd905a
--- /dev/null
+++ b/lisp/international/utf-7.el
@@ -0,0 +1,143 @@
+;;; utf-7.el --- utf-7 coding system
+
+;; Copyright (C) 2003  Free Software Foundation, Inc.
+
+;; Author: Dave Love <fx@gnu.org>
+;; Keywords: i18n, mail
+
+;; This file 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, or (at your option)
+;; any later version.
+
+;; This file is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with GNU Emacs; see the file COPYING.  If not, write to
+;; the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+;; Boston, MA 02111-1307, USA.
+
+;;; Commentary:
+
+;; Defines a coding system for UTF-7, defined in RFC 2152.  Non-ASCII
+;; segments are encoded as base64-encoded big endian UTF-16.  Also
+;; defines a variation required for IMAP (RFC 2060).
+
+;; The encoding and decoding was originally taken from Jon K Hellan's
+;; implementation in Gnus, but has been substantially re-done.
+
+;; This probably needs more attention.  In particular, it's not
+;; completely consistent with iconv's behaviour.  It's arguable
+;; whether the IMAP version should be a coding system since it's
+;; apparently only used for IMAP mailbox names.
+
+;;; Code:
+
+;; See mule-conf.
+;; (define-coding-system 'utf-7
+;;   "UTF-7 encoding of Unicode (RFC 2152)"
+;;   :coding-type 'utf-8
+;;   :mnemonic ?U
+;;   :mime-charset 'utf-7
+;;   :charset-list '(unicode)
+;;   :pre-write-conversion 'utf-7-pre-write-conversion
+;;   :post-read-conversion 'utf-7-post-read-conversion)
+
+;; (define-coding-system 'utf-7-imap
+;;   "UTF-7 encoding of Unicode, IMAP version (RFC 2060)"
+;;   :coding-type 'utf-8
+;;   :mnemonic ?U
+;;   :mime-charset 'utf-7
+;;   :charset-list '(unicode)
+;;   :pre-write-conversion 'utf-7-imap-pre-write-conversion
+;;   :post-read-conversion 'utf-7-imap-post-read-conversion))
+
+;;;###autoload
+(defun utf-7-decode (len imap)
+  "Decode LEN bytes of UTF-7 at point.
+IMAP non-nil means use the IMAP version."
+  (save-excursion
+    (save-restriction
+      (narrow-to-region (point) (+ (point) len))
+      (let ((not-esc (if imap "^&" "^+"))
+            (skip-chars (if imap "A-Za-z0-9+," "A-Za-z0-9+/")))
+        (while (not (eobp))
+          (skip-chars-forward not-esc)
+          (unless (eobp)
+            (forward-char)
+            (let ((p (point))
+                  (run-length (skip-chars-forward skip-chars)))
+              (if (eq ?- (char-after))
+                  (delete-char 1))
+              (unless (= run-length 0)  ; encoded lone esc-char
+                (let ((pl (mod (- run-length) 4)))
+                  (insert-char ?= pl)
+                  (if imap
+                      (subst-char-in-region p (point) ?, ?/))
+                  (base64-decode-region p (point)))
+                (decode-coding-region p (point) 'utf-16-be)
+                (save-excursion
+                  (goto-char p)
+                  (delete-backward-char 1)))))))
+      (- (point-max) (point-min)))))
+
+(defun utf-7-post-read-conversion (len)
+  (utf-7-decode len nil))
+
+(defun utf-7-imap-post-read-conversion (len)
+  (utf-7-decode len t))
+
+;;;###autoload
+(defun utf-7-encode (from to imap)
+  "Encode bytes between FROM and TO to UTF-7.
+ESC and SKIP-CHARS are adjusted for the normal and IMAP versions."
+  (let* ((old-buf (current-buffer))
+         (esc (if imap ?& ?+))
+         ;; These are characters which can be encoded asis.
+         (skip-chars (if imap
+                         "\t\n\r\x20-\x25\x27-\x7e" ; rfc2060 
+                       ;; This includes the rfc2152 optional set.
+                       ;; Perhaps it shouldn't (like iconv).
+                       "\t\n\r -*,-[]-}"))
+         (not-skip-chars (format "^%s%c" skip-chars esc)))
+    (set-buffer (generate-new-buffer " *temp*"))
+    (if (stringp from)
+        (insert from)
+      (insert-buffer-substring old-buf from to))
+    (goto-char (point-min))
+    (while (not (eobp))
+      (skip-chars-forward skip-chars)
+      (if (eq ?+ (char-after))
+          (progn (forward-char)
+                 (insert ?-))
+        (unless (eobp)
+          (insert esc)
+          (let ((p (point)))
+            (skip-chars-forward not-skip-chars)
+            (save-restriction
+              ;; encode-coding-region doesn't preserve point
+              (narrow-to-region p (point))
+              (encode-coding-region p (point-max) 'utf-16-be)
+              (base64-encode-region p (point-max))
+              (if imap
+                  (subst-char-in-region p (point-max) ?/ ?,))
+              (goto-char p)
+              ;; As I read the RFC, this isn't correct, but it's
+              ;; consistent with iconv, at least regarding `='.
+              (skip-chars-forward "^= \t\n")
+              (delete-region (point) (point-max))))
+          (unless (eobp)
+            (insert ?-)))))
+    nil))
+
+(defun utf-7-pre-write-conversion (from to)
+  (utf-7-encode from to nil))
+
+(defun utf-7-imap-pre-write-conversion (from to)
+  (utf-7-encode from to t))
+
+(provide 'utf-7)
+;;; utf-7.el ends here