For myself, contrarily to what I thought at first try,
(latin-unity-install) did not solve the problem.
So I have hacked lisp/gnus/mm-util.el with this patch :
D:\Local\XEmacs\site-packages\lisp\gnus>diff -u mm-util.el~ mm-util.el
--- mm-util.el~ Fri Sep 27 13:49:10 2002
+++ mm-util.el Fri Sep 27 19:58:08 2002
@@ -531,6 +531,9 @@
(mapcar 'mm-mime-charset
(delq 'ascii
(mm-find-charset-region b e))))))
+ (if (and (memq 'iso-8859-1 charsets)
+ (memq 'iso-8859-9 charsets))
+ (push 'iso-8859-15 charsets))
(if (and (memq 'iso-8859-15 charsets)
(memq 'iso-8859-15 hack-charsets)
(save-excursion (mm-iso-8859-x-to-15-region b e)))
But this is ugly. Probably the truth is somewhere else.
--
Fabrice