diff --git a/reference/sem/functions/msg-send.xml b/reference/sem/functions/msg-send.xml
index 80b3b9182f..cdeb91e91a 100644
--- a/reference/sem/functions/msg-send.xml
+++ b/reference/sem/functions/msg-send.xml
@@ -13,8 +13,8 @@
    <methodparam><type>resource</type><parameter>queue</parameter></methodparam>
    <methodparam><type>int</type><parameter>msgtype</parameter></methodparam>
    <methodparam><type>mixed</type><parameter>message</parameter></methodparam>
-   <methodparam choice="opt"><type>bool</type><parameter>serialize</parameter></methodparam>
-   <methodparam choice="opt"><type>bool</type><parameter>blocking</parameter></methodparam>
+   <methodparam choice="opt"><type>bool</type><parameter>serialize</parameter><initializer>true</initializer></methodparam>
+   <methodparam choice="opt"><type>bool</type><parameter>blocking</parameter><initializer>true</initializer></methodparam>
    <methodparam choice="opt"><type>int</type><parameter role="reference">errorcode</parameter></methodparam>
   </methodsynopsis>
   <para>