diff -up fetchmail-6.3.26/socket.c.orig fetchmail-6.3.26/socket.c
--- fetchmail-6.3.26/socket.c.orig	2018-08-06 13:01:04.859681651 +0200
+++ fetchmail-6.3.26/socket.c	2018-08-06 13:00:55.005670522 +0200
@@ -1050,6 +1050,8 @@ int SSLOpen(int sock, char *mycert, char
         	SSL_use_RSAPrivateKey_file(_ssl_context[sock], mykey, SSL_FILETYPE_PEM);
 	}
 
+	SSL_set_tlsext_host_name(_ssl_context[sock], servercname);
+
 	if (SSL_set_fd(_ssl_context[sock], sock) == 0 
 	    || SSL_connect(_ssl_context[sock]) < 1) {
 		ERR_print_errors_fp(stderr);