diff.el Emacs version problem

[Zajcev Evgeny <zevlg@xxxxxxxxx>]

diff.el defines some internal variable `diff-emacs-19-p' like this:

    (defconst diff-emacs-19-p
      (let ((ver (string-to-int (substring emacs-version 0 2))))
        (>= ver 19)))

As you can see we will get nil `diff-emacs-19-p' value under SXEmacs.
This can cause problems to SXEmacs.

We can have simple fix like this:

    (defconst diff-emacs-19-p
      (let ((ver (string-to-int (substring emacs-version 0 2))))
        (or (zerop ver) (>= ver 19))))

ver will be set to 0 if first character in `emacs-version' is
non-digit.

Thanks!

-- 
lg