See https://bugs.debian.org/854210
--- a/sendxmpp
+++ b/sendxmpp
@@ -299,7 +299,7 @@
 		'interactive'	=> ($interactive or 0),
 		'tls'			=> ($tls or 0),
 		'no-tls-verify'	=> ($no_tls_verify or 0),
-		'tls-ca-path'	=> ($tls_ca_path or ''),
+		'tls-ca-path'	=> ($tls_ca_path or '/etc/ssl/certs'),
 		'ssl'			=> ($ssl or 0),
 		'debug'			=> ($debug or 0),
 		'verbose'		=> ($verbose or 0),