mysqld_multi doesn't support !include or !includedir directives

Hi,

I try to use !includedir directive with mysqld_multi for load  other option files but nothing is loaded by mysql.

In the default my.cnf, I have only the includedir directive for my configuration directory :

!includedir /etc/my.cnf.d

And in /etc/my.cnf.d/mysql3306.cnf I have :

[mysqld_multi]
mysqld     = /usr/bin/mysqld_safe
mysqladmin = /usr/bin/mysqladmin
user       = toto
password   = toto
log        = /var/log/mysqld_multi.log

[mysqld3306]
port                             = 3306
socket                           = /var/lib/mysql_3306/mysql.sock
pid-file                         = /var/lib/mysql_3306/test.pid
datadir                          = /var/lib/mysql_3306
tmpdir                           = /tmp
user                             = mysql
mysqld                           = /usr/sbin/mysqld
log-error                        = /var/lib/mysql_3306/test.err

But mysqld_multi doesn't not load  mysql3306.cnf file.

# service mysqld_multi report
Reporting MySQL servers
No groups to be reported (check your GNRs)

Whereas

# my_print_defaults --defaults-file=/etc/my.cnf mysqld3306
--port=3306
--socket=/var/lib/mysql_3306/mysql.sock
--pid-file=/var/lib/mysql_3306/test.pid
--datadir=/var/lib/mysql_3306
--tmpdir=/tmp
--user=mysql

I found the Bug #29327 dated 2007 but without fix.

I use mysqld_multi log file version 2.16 and MySQL 5.6.24 on CentOS 6.

Someone as an idea please? Where is my mistake?

Regards,
Thomas