conn.go.diff

diff --git a/client.go b/client.go
index 7842cfc..a12f4ba 100644
--- a/client.go
+++ b/client.go
@@ -47,6 +47,7 @@ func (c *Client) Exchange(m *Msg, a string) (r *Msg, rtt time.Duration, err erro
   if err = w.dial(); err != nil {
 		return nil, 0, err
 	}
+	defer w.close()
 	if err = w.send(m); err != nil {
 		return nil, 0, err
 	}
@@ -267,6 +268,10 @@ func (w *reply) write(p []byte) (n int, err error) {
 	return
 }
 
+func (w *reply) close() {
+	w.conn.Close()
+}
+
 func setTimeouts(w *reply) {
 	if w.client.ReadTimeout == 0 {
 		w.conn.SetReadDeadline(time.Now().Add(2 * 1e9))