diff --git a/include/mbedtls/ssl_internal.h b/include/mbedtls/ssl_internal.h
index d214703..68b5f30 100644
--- a/include/mbedtls/ssl_internal.h
+++ b/include/mbedtls/ssl_internal.h
@@ -559,6 +559,7 @@
 int mbedtls_ssl_read_record( mbedtls_ssl_context *ssl );
 int mbedtls_ssl_fetch_input( mbedtls_ssl_context *ssl, size_t nb_want );
 
+int mbedtls_ssl_write_handshake_msg( mbedtls_ssl_context *ssl );
 int mbedtls_ssl_write_record( mbedtls_ssl_context *ssl );
 int mbedtls_ssl_flush_output( mbedtls_ssl_context *ssl );