diff -rupN /il2/users/yaakovk/tests/X/xcblock/libX11-1.2/src/xcb_io.c libX11/src/xcb_io.c
--- /il2/users/yaakovk/tests/X/xcblock/libX11-1.2/src/xcb_io.c	2009-02-17 16:24:40.000000000 +0200
+++ libX11/src/xcb_io.c	2010-01-17 16:17:31.000000000 +0200
@@ -120,6 +120,25 @@ static void call_handlers(Display *dpy, 
 	    _XError(dpy, (xError *) buf);
 }
 
+static int check_for_waiting_request(Display * dpy, xcb_generic_event_t * event)
+{
+	int ret = 0;
+	if (dpy->xcb->pending_requests != 0 && event->response_type == X_Error)
+	{
+		PendingRequest* pr = dpy->xcb->pending_requests;
+		while (pr != NULL && !ret)
+		{
+			if (XLIB_SEQUENCE_COMPARE(pr->sequence, ==, event->full_sequence))
+			{
+				pr->reply = event;
+				ret = 1;
+			}
+			pr = pr->next;
+		}
+	}
+	return ret;
+}
+
 static xcb_generic_event_t * wait_or_poll_for_event(Display *dpy, int wait)
 {
 	xcb_connection_t *c = dpy->xcb->connection;
@@ -138,6 +157,8 @@ static xcb_generic_event_t * wait_or_pol
 			event = xcb_wait_for_event(c);
 			LockDisplay(dpy);
 			dpy->xcb->event_waiter = 0;
+			if (check_for_waiting_request(dpy, event))
+				event = NULL;
 			ConditionBroadcast(dpy, dpy->xcb->event_notify);
 		}
 	}
@@ -171,6 +192,8 @@ static void process_responses(Display *d
 	{
 		PendingRequest *req = dpy->xcb->pending_requests;
 		unsigned long event_sequence = dpy->last_request_read;
+		while (req && req->reply)
+			req = req->next;
 		if(event)
 			widen(&event_sequence, event->full_sequence);
 		assert(!(req && current_request && !XLIB_SEQUENCE_COMPARE(req->sequence, <=, current_request)));
@@ -215,7 +238,7 @@ static void process_responses(Display *d
 		else if(req && xcb_poll_for_reply(dpy->xcb->connection, req->sequence, &reply, &error))
 		{
 			unsigned int sequence = req->sequence;
-			if(!reply)
+			if(!reply && !req->reply)
 			{
 				dpy->xcb->pending_requests = req->next;
 				if(!dpy->xcb->pending_requests)
@@ -426,9 +449,35 @@ static PendingRequest * insert_pending_r
 			dpy->xcb->pending_requests_tail = &(node->next);
 		*cur = node;
 	}
+	(*cur)->reply = 0;
 	return *cur;
 }
 
+static void remove_pending_request(Display* dpy, PendingRequest* req)
+{
+	PendingRequest *pr = dpy->xcb->pending_requests;
+	if (pr == req)
+	{
+		dpy->xcb->pending_requests = pr->next;
+		if (!dpy->xcb->pending_requests)
+			dpy->xcb->pending_requests_tail = &dpy->xcb->pending_requests;
+	}
+	else
+	{
+		while (pr)
+		{
+			if (pr->next == req)
+			{
+				pr->next = req->next;
+				if (!pr->next)
+					dpy->xcb->pending_requests_tail = &(pr->next);
+			}
+			pr = pr->next;
+		}
+		free(req);
+	}
+}
+
 /*
  * _XReply - Wait for a reply packet and copy its contents into the
  * specified rep.
@@ -447,14 +496,30 @@ Status _XReply(Display *dpy, xReply *rep
 	if(dpy->flags & XlibDisplayIOError)
 		return 0;
 
-	_XSend(dpy, NULL, 0);
 	current = insert_pending_request(dpy);
+	_XSend(dpy, NULL, 0);
 	/* FIXME: drop the Display lock while waiting?
 	 * Complicates process_responses. */
 	reply = xcb_wait_for_reply(c, current->sequence, &error);
+	if (reply == NULL && error == NULL)
+	{
+		if(dpy->xcb->event_waiter && current->reply == NULL)
+		{
+			ConditionWait(dpy, dpy->xcb->event_notify);
+		}
+		if (current->reply != NULL && current->reply->response_type == X_Error)
+		{
+			if (current->reply->response_type == X_Error)
+				error = (xcb_generic_error_t *)current->reply;
+			else
+				reply = (char*)current->reply;
+			remove_pending_request(dpy, current);
+		}
+	}
 
 	check_internal_connections(dpy);
-	process_responses(dpy, 0, &error, current->sequence);
+	if (error == NULL)
+		process_responses(dpy, 0, &error, current->sequence);
 
 	if(error)
 	{
diff -rupN /il2/users/yaakovk/tests/X/xcblock/libX11-1.2/src/Xxcbint.h libX11/src/Xxcbint.h
--- /il2/users/yaakovk/tests/X/xcblock/libX11-1.2/src/Xxcbint.h	2009-02-02 18:34:16.000000000 +0200
+++ libX11/src/Xxcbint.h	2010-01-17 16:17:28.000000000 +0200
@@ -16,6 +16,7 @@ typedef struct PendingRequest PendingReq
 struct PendingRequest {
 	PendingRequest *next;
 	unsigned long sequence;
+	xcb_generic_event_t* reply;
 };
 
 typedef struct _X11XCBPrivate {