#15 graph name in servicextinfo

[Regis Rampnoux]

Is it possible to use only one URL definition for the
same service in serviceextinfo?

like:
define serviceextinfo{
host_name server1,
server2, server3
service_description Room service
notes_url
http://localhost/nagiostat/nagiostat.cgi?graph_name=$HOSTNAME-http
icon_image graph.gif
icon_image_alt View graphs
}

where $HOSTNAME is the server name of course...
Or something which can achieve this...
(hostgroups support should be of interest also)