diff --git a/reference/datetime/functions/date-add.xml b/reference/datetime/functions/date-add.xml
index 2644e78e2d..2ca6cdae5d 100644
--- a/reference/datetime/functions/date-add.xml
+++ b/reference/datetime/functions/date-add.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="iso-8859-1"?>
-<!-- $Revision: 1.3 $ -->
+<!-- $Revision: 1.4 $ -->
 <refentry xml:id="function.date-add" xmlns="http://docbook.org/ns/docbook">
  <refnamediv>
   <refname>date_add</refname>
@@ -14,7 +14,7 @@
   <methodsynopsis>
    <type>void</type><methodname>date_add</methodname>
    <methodparam><type>DateTime</type><parameter>object</parameter></methodparam>
-   <methodparam><type>DateInterval</type><parameter>object</parameter></methodparam>
+   <methodparam><type>DateInterval</type><parameter>interval</parameter></methodparam>
   </methodsynopsis>
   <para>
    Adds the specified DateInterval object to the specified DateTime object.
@@ -37,7 +37,7 @@
     </varlistentry>
     <varlistentry>
      <term>
-      <parameter>object</parameter>
+      <parameter>internal</parameter>
      </term>
      <listitem>
       <para>
diff --git a/reference/datetime/functions/date-sub.xml b/reference/datetime/functions/date-sub.xml
index 3c8f90aecf..f3344f8fb1 100644
--- a/reference/datetime/functions/date-sub.xml
+++ b/reference/datetime/functions/date-sub.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="iso-8859-1"?>
-<!-- $Revision: 1.3 $ -->
+<!-- $Revision: 1.4 $ -->
 <refentry xml:id="function.date-sub" xmlns="http://docbook.org/ns/docbook">
  <refnamediv>
   <refname>date_sub</refname>
@@ -14,7 +14,7 @@
   <methodsynopsis>
    <type>void</type><methodname>date_sub</methodname>
    <methodparam><type>DateTime</type><parameter>object</parameter></methodparam>
-   <methodparam><type>DateInterval</type><parameter>object</parameter></methodparam>
+   <methodparam><type>DateInterval</type><parameter>interval</parameter></methodparam>
   </methodsynopsis>
   <para>
    Subtracts the specified DateInterval object from the specified DateTime
@@ -38,7 +38,7 @@
     </varlistentry>
     <varlistentry>
      <term>
-      <parameter>object</parameter>
+      <parameter>interval</parameter>
      </term>
      <listitem>
       <para>