diff --git a/doc/src/sgml/protocol.sgml b/doc/src/sgml/protocol.sgml
index a746c967053..721af948098 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;"
Byte1('v')
- 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.
@@ -5336,8 +5339,9 @@ psql "dbname=postgres replication=database" -c "IDENTIFY_SYSTEM;"
Int32
- Newest minor protocol version supported by the server
- for the major protocol version requested by the client.
+ Latest major and minor version supported by the server.
+ The most significant 16 bits are the major version number, and the least
+ significant 16 bits are the minor version number.