diff --git a/doc/src/sgml/protocol.sgml b/doc/src/sgml/protocol.sgml
index a746c967053..0bcece34b2a 100644
--- a/doc/src/sgml/protocol.sgml
+++ b/doc/src/sgml/protocol.sgml
@@ -5317,7 +5317,10 @@ psql "dbname=postgres replication=database" -c "IDENTIFY_SYSTEM;"
        <term>Byte1('v')</term>
        <listitem>
         <para>
-         Identifies the message as a protocol version negotiation
+         Identifies the message as a protocol version negotiation.
+         The server sends this message if the requested protocol is 
+         not equal to the version the server supports or the client
+         requests protocol options that are not recognized.
          message.
         </para>
        </listitem>
@@ -5336,8 +5339,10 @@ psql "dbname=postgres replication=database" -c "IDENTIFY_SYSTEM;"
        <term>Int32</term>
        <listitem>
         <para>
-         Newest minor protocol version supported by the server
-         for the major protocol version requested by the client.
+         The protcol version requested by the client unless it is higher than the
+         latest version we support in which case the latest protocol version we support.
+         The most significant 16 bits are the major version number, and the least
+         significant 16 bits are the minor version number.
         </para>
        </listitem>
       </varlistentry>