--- a/xml/en/docs/ngx_core_module.xml
+++ b/xml/en/docs/ngx_core_module.xml
@@ -54,11 +54,12 @@ Mainly used during development.
 Enables debugging log for selected client connections.
 Other connections will use logging level set by the
 <link id="error_log"/> directive.
-Debugged connections are specified by IPv4 or IPv6 (1.3.0) address or network.
+Debugged connections are specified by IPv4 or IPv6 (1.3.0, 1.2.1)
+address or network.
 A connection may also be specified using a hostname, in which case the
 first IPv4 address corresponding to a name is used.
-For connections using UNIX-domain sockets (1.3.0), debugging log is enabled
-by the “<literal>unix:</literal>” parameter.
+For connections using UNIX-domain sockets (1.3.0, 1.2.1),
+debugging log is enabled by the “<literal>unix:</literal>” parameter.
 <example>
 events {
     debug_connection 127.0.0.1;