diff --git a/lisp/spam.el b/lisp/spam.el
index 097299f..5f11fad 100644
--- a/lisp/spam.el
+++ b/lisp/spam.el
@@ -1432,7 +1432,7 @@ addition to the set values for the group."
 	 (gnus-check-backend-function
 	  'request-move-article gnus-newsgroup-name))
 	(respool-method (gnus-find-method-for-group gnus-newsgroup-name))
-	article mark deletep respool)
+	article mark deletep respool invalid-move-destination)
 
     (when (member 'respool groups)
       (setq respool t)			; boolean for later
@@ -1440,7 +1440,31 @@ addition to the set values for the group."
 
     ;; now do the actual move
     (dolist (group groups)
-      (when (and articles (stringp group))
+
+      (setq invalid-move-destination
+            (or
+             (and
+              (eq classification 'spam)
+              (spam-group-spam-contents-p gnus-newsgroup-name)
+              (spam-group-spam-contents-p group)
+              (gnus-message
+               3
+               "Sorry, can't move spam from spam group %s to spam group %s"
+               gnus-newsgroup-name
+               group))
+             (and
+              (eq classification 'ham)
+              (spam-group-ham-contents-p gnus-newsgroup-name)
+              (spam-group-ham-contents-p group)
+              (gnus-message
+               3
+               "Sorry, can't move ham from ham group %s to ham group %s"
+               gnus-newsgroup-name
+               group))))
+
+      (when (and articles
+                 (stringp group)
+                 (not invalid-move-destination))
 
 	;; first, mark the article with the process mark and, if needed,
 	;; the unread or expired mark (for ham and spam respectively)