`m m' from a log-all buffer got me this backtrace:
---------
Debugger entered--Lisp error: (wrong-type-argument sequencep t)
concat("Merge" t)
(magit-read-rev (concat "Merge" (magit-guess-branch)))
(list (magit-read-rev (concat "Merge" ...)))
call-interactively(magit-merge)
magit-key-mode-command(magit-merge)
(lambda nil (interactive) (magit-key-mode-command (quote magit-merge)))()
call-interactively((lambda nil (interactive) (magit-key-mode-command (quote
magit-merge))) nil nil)
---------
Note that I never got prompted to enter a revision to merge with
--
Dave Abrahams
BoostPro Computing
http://www.boostpro.com