diff --git a/programs/ssl/ssl_server2.c b/programs/ssl/ssl_server2.c
index bc97149..6d81626 100644
--- a/programs/ssl/ssl_server2.c
+++ b/programs/ssl/ssl_server2.c
@@ -791,6 +791,7 @@
     return( mbedtls_net_send( io_ctx->net, buf, len ) );
 }
 
+#if defined(SNI_OPTION) || !defined(MBEDTLS_SSL_CONF_AUTHMODE)
 /*
  * Return authmode from string, or -1 on error
  */
@@ -805,6 +806,7 @@
 
     return( -1 );
 }
+#endif /* SNI_OPTION || !MBEDTLS_SSL_CONF_AUTHMODE */
 
 /*
  * Used by sni_parse and psk_parse to handle coma-separated lists