http://www.emacswiki.org/cgi-bin/wiki.pl より．
(defun browse-url-mozilla-new-tab (url &optional new-window)
;; new-window ignored
"Open URL in a new tab in Mozilla."
(interactive (browse-url-interactive-arg "URL: "))
(unless
(string= ""
(shell-command-to-string
(concat "mozilla -remote 'openURL(" url ",new-tab)'")))
(message "Starting Mozilla...")
(start-process (concat "mozilla " url) nil "mozilla" url)
(message "Starting Mozilla...done")))
(setq browse-url-browser-function 'browse-url-mozilla-new-tab)