Cannot start w3m-el from within a document, except newsfeeds

[Hermann]

Hi,
the subject almost says it:
When I open a link from within a news feed, w3m-el starts as expected.
However: When I try to open a link from any other document (post/email),
I get the message:
Mozilla starting...
and of course nothing happens; I use Gnus from a text console.
My .gnus reads the following, regarding w3m-el:

  (eval-after-load "w3"
    '(progn
      (fset 'w3-fetch-orig (symbol-function 'w3-fetch))
      (defun w3-fetch (&optional url target)
        (interactive (list (w3-read-url-with-default)))
        (if (eq major-mode 'gnus-article-mode)
            (browse-url url)
          (w3-fetch-orig url target)))))

So what do I have to insert in .gnus or in .emacs?
Hermann

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