Display as coding changes root of tree

[Peter Breitfeld]

I run in the following minor problem. Some messages/articles I get are in wrong
encoding. So I wrote the following function to display these in
different encoding:

----cut---------8<----start-------8<---------------- 
(setq gnus-summary-show-article-charset-alist
  '((1 . iso-8859-1)
    (2 . cp1252)
    (8 . utf-8)
    (9 . iso-8859-9)))

(defun brf-view-article-as-charset ()
  (interactive)
  (message "Anzeige in: latin-[1], latin-[9]/15, utf-[8], cp125[2]")
  (let ((answer (read-char)))
    (cond
     ((eq answer ?1)
      (gnus-summary-show-article 1))
     ((eq answer ?9)
      (gnus-summary-show-article 9))
     ((eq answer ?2)
      (gnus-summary-show-article 2))
     ((eq answer ?8)
      (gnus-summary-show-article 8))))
  (gnus-summary-rethread-current))

(define-key gnus-summary-mode-map "v" 'brf-view-article-as-charset) 
----cut---------8<----start-------8<----------------

This displays the article in the wanted encoding. But in the summary
tree the article gets shifted to the left and becomes the new root of
the following articles in the thread.
First I suspected, that the call of gnus-summary-rethread-current is the
reason of that behaviour, but not calling it or using the menu
Article/Display... to change the display shows the same effect.

Does anyone know how to change the display of the article without any
changes in the summary tree?

TIA

-- 
_________________________________________________________________
Peter Breitfeld, Bad Saulgau, Germany -- http://www.pBreitfeld.de