Index: src/vortex_sequencer.c
===================================================================
--- src/vortex_sequencer.c	(revision 3394)
+++ src/vortex_sequencer.c	(working copy)
@@ -110,6 +110,7 @@
 	int                   size_to_copy;
 	char                * a_frame;
 	bool                  resequence;
+	bool				  throttling;
 	VortexAsyncQueue    * queue;
 
 	while (true) {
@@ -276,6 +277,19 @@
 			size_to_copy = max_seq_no - next_seq_no + 1;
 		else
 			size_to_copy = message_size;
+		
+		/* limit sent size to 1kbyte, as recommended by RFC 3081, sec. 3.1.4.
+		 * This improves throughput by making it less likely for the window to fill up,
+		 * and by avoiding bad interactions with TCP's own flow control.
+		 * However, to work around Vortex problems with split greetings messages,
+		 * we avoid doing this on channel 0. (This workaround can be taken out
+		 * when the underlying problem with greetings parsing is fixed.) */
+		if( size_to_copy > 1024 && data->channel_num != 0 ) {
+			size_to_copy = 1024;
+			throttling = true;
+		} else {
+			throttling = false;
+		}
 
 		/* create the new package to be managed by the vortex writer */
 		packet.type         = data->type;
@@ -355,6 +369,13 @@
 				vortex_channel_queue_pending_message (channel, data);
 			}
 			
+			if (throttling) {
+				/* there's room in the window but we've queued the message as pending anyway,
+				 * to avoid filling the window. Need to send myself a resequence signal
+				 * so I will wake up immediately and send the next fragment. */
+				vortex_sequencer_signal_update(channel);
+			}
+			
 			/* because we have queued the message, we want
 			 * to avoid the message to be deleted from the
 			 * last instruction this while has.