diff --git a/includes/xmlrpcs.inc b/includes/xmlrpcs.inc
index 118f652..8655c05 100644
--- a/includes/xmlrpcs.inc
+++ b/includes/xmlrpcs.inc
@@ -9,7 +9,9 @@
  * Invokes XML-RPC methods on this server.
  *
  * @param array $callbacks
- *   Array of external XML-RPC method names with the callbacks they map to.
+ *   Either an associative array of external XML-RPC method names as keys with
+ *   the callbacks they map to as values, or a more complex structure
+ *   describing XML-RPC callbacks as returned from hook_xmlrpc().
  */
 function xmlrpc_server($callbacks) {
   $xmlrpc_server = new stdClass();