in `gnus-original-article-mode'.
(mime-preview-over-to-previous-method-alist): Use `gnus-summary-prev-article'
in `gnus-original-article-mode'.
 (set-alist 'mime-preview-following-method-alist
           'gnus-original-article-mode #'gnus-following-method)
 
+(set-alist 'mime-preview-over-to-previous-method-alist
+          'gnus-original-article-mode
+          (lambda ()
+            (gnus-article-read-summary-keys
+             nil (gnus-character-to-event ?P))))
+
+(set-alist 'mime-preview-over-to-next-method-alist
+          'gnus-original-article-mode'
+          (lambda ()
+            (gnus-article-read-summary-keys
+             nil (gnus-character-to-event ?N))))
+
 
 ;;; @ end
 ;;;