--- nnfolder.el	Sat Jul  1 13:10:51 2000
+++ nnfolder-new.el	Sat Dec 30 13:42:16 2000
@@ -118,18 +118,20 @@
 	(goto-char (point-min))
 	(if (stringp (car articles))
 	    'headers
-	  (while (setq article (pop articles))
-	    (set-buffer nnfolder-current-buffer)
-	    (when (nnfolder-goto-article article)
-	      (setq start (point))
-	      (setq stop (if (search-forward "\n\n" nil t)
-			     (1- (point))
-			   (point-max)))
-	      (set-buffer nntp-server-buffer)
-	      (insert (format "221 %d Article retrieved.\n" article))
-	      (insert-buffer-substring nnfolder-current-buffer start stop)
-	      (goto-char (point-max))
-	      (insert ".\n")))
+	  (let ((existing-articles (nnfolder-existing-articles)))
+	    (while (setq article (pop articles))
+	      (when (member article existing-articles)
+		(set-buffer nnfolder-current-buffer)
+		(when (nnfolder-goto-article article)
+		  (setq start (point))
+		  (setq stop (if (search-forward "\n\n" nil t)
+				 (1- (point))
+			       (point-max)))
+		  (set-buffer nntp-server-buffer)
+		  (insert (format "221 %d Article retrieved.\n" article))
+		  (insert-buffer-substring nnfolder-current-buffer start stop)
+		  (goto-char (point-max))
+		  (insert ".\n")))))
 
 	  (set-buffer nntp-server-buffer)
 	  (nnheader-fold-continuation-lines)