diff --git a/.travis.yml b/.travis.yml
index 7fe84a2..9e600b2 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,7 +6,13 @@ php:
   - 5.6
   - 7.0
   - 7.1
-  - hhvm
+
+matrix:
+  include:
+    - php: hhvm
+      dist: trusty
+  allow_failures:
+    - php: hhvm
 
 before_script:
   - sh -c 'if [ "$TRAVIS_PHP_VERSION" != "hhvm" ]; then echo "session.serialize_handler = php" >> ~/.phpenv/versions/$(phpenv version-name)/etc/php.ini; fi;'
diff --git a/src/Ratchet/Wamp/Topic.php b/src/Ratchet/Wamp/Topic.php
index 3fe73d1..7bde5e0 100644
--- a/src/Ratchet/Wamp/Topic.php
+++ b/src/Ratchet/Wamp/Topic.php
@@ -38,7 +38,7 @@ class Topic implements \IteratorAggregate, \Countable {
 
     /**
      * Send a message to all the connections in this topic
-     * @param string $msg Payload to publish
+     * @param string|array $msg Payload to publish
      * @param array $exclude A list of session IDs the message should be excluded from (blacklist)
      * @param array $eligible A list of session Ids the message should be send to (whitelist)
      * @return Topic The same Topic object to chain