diff --git a/lisp/international/mule-conf.el b/lisp/international/mule-conf.el
index 8b78952cd43..7b3ad79772f 100644
--- a/lisp/international/mule-conf.el
+++ b/lisp/international/mule-conf.el
@@ -1419,6 +1419,14 @@ for decoding and encoding files, process I/O, etc."
   :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
+  :charset-list '(unicode)
+  :pre-write-conversion 'utf-7-imap-pre-write-conversion
+  :post-read-conversion 'utf-7-imap-post-read-conversion)
+
 ;; Use us-ascii for terminal output if some other coding system is not
 ;; specified explicitly.
 (set-safe-terminal-coding-system-internal 'us-ascii)