diff --git a/lisp/vc/vc-hooks.el b/lisp/vc/vc-hooks.el
index 76d97716724..cc08767ade3 100644
--- a/lisp/vc/vc-hooks.el
+++ b/lisp/vc/vc-hooks.el
@@ -99,7 +99,7 @@ interpreted as hostnames."
   :type 'regexp
   :group 'vc)
 
-(defcustom vc-handled-backends '(RCS CVS SVN SCCS SRC Bzr Git Hg Mtn)
+(defcustom vc-handled-backends '(RCS CVS SVN SCCS SRC Bzr Git Hg)
   ;; RCS, CVS, SVN, SCCS, and SRC come first because they are per-dir
   ;; rather than per-tree.  RCS comes first because of the multibackend
   ;; support intended to use RCS for local commits (with a remote CVS server).