diff --git a/testsite/tls/templates/xmpp.example.com_xmpp.cfg b/testsite/tls/templates/xmpp.example.com_xmpp.cfg
index ad7b4ed3a372cba044dc66a03899fbbafc527812..d35b85b0c6f54d4629aad9a456cda9cbd786f738 100644
--- a/testsite/tls/templates/xmpp.example.com_xmpp.cfg
+++ b/testsite/tls/templates/xmpp.example.com_xmpp.cfg
@@ -25,3 +25,8 @@ tls_www_server
 # Whether this certificate will be used to sign data (needed
 # in TLS DHE ciphersuites).
 signing_key
+
+# Whether this certificate will be used to encrypt data (needed
+# in TLS RSA ciphersuites). Note that it is preferred to use different
+# keys for encryption and signing.
+encryption_key