In templates.conf I can read (sorry to paste here the text):

#  A section can reference a template by using "$template name"
. . .

#  Then, each "home_server" section in "proxy.conf" would
#  only list the IP address of that home server, and a
#  line saying
#
#             template = example.com

I use the way you told me:

### /etc/freeradius/proxy.conf
home_server tld-rediris1 {
        $template tld-rediris
        ipaddr = YYY
}

But doesn't work;

/etc/freeradius# freeradius -X
FreeRADIUS Version 2.0.4, for host x86_64-pc-linux-gnu, built on Oct 20 2009 at 11:45:11
Copyright (C) 1999-2008 The FreeRADIUS server project and contributors.
There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE.
You may redistribute copies of FreeRADIUS under the terms of the
GNU General Public License.
Starting - reading configuration files ...
including configuration file /etc/freeradius/radiusd.conf
including configuration file /etc/freeradius/templates.conf
including configuration file /etc/freeradius/proxy.conf
WARNING: No such configuration item tld-rediris
/etc/freeradius/proxy.conf[28]: Reference "tld-rediris" not found
Errors reading /etc/freeradius/radiusd.conf