diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index 88a4f5a..0f4fd6c 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -455,6 +455,17 @@
     time_t t;
 #endif
 
+    /*
+     * When responding to a verify request, MUST reuse random (RFC 6347 4.2.1)
+     */
+#if defined(POLARSSL_SSL_PROTO_DTLS)
+    if( ssl->transport == SSL_TRANSPORT_DATAGRAM &&
+        ssl->handshake->verify_cookie != NULL )
+    {
+        return( 0 );
+    }
+#endif
+
 #if defined(POLARSSL_HAVE_TIME)
     t = time( NULL );
     *p++ = (unsigned char)( t >> 24 );