Least Significant Bit

Michael Klishin have deviced a cucumber-mode.el mode for Emacs that provides all the sweet syntax hightlights and yasnippets snippets. You clone it or download it, throw it in your elisp/ directory and then adding this to your .emacs you’ll get all the goodies:

(add-to-list 'load-path "~/.emacs.d/elisp/cucumber-mode")
;; and load it
(autoload 'cucumber-mode "cucumber-mode" "Mode for editing cucumber files" t)
(add-to-list 'feature-mode '("\.feature$" . cucumber-mode))

I even made myself busy and added But support with:

   '("^ *But" . font-lock-keyword-face)

also the installation snippet was added as comment on top of the file.

update

Michael have pushed my changes into official repo :-)