D.1. README.ruby_init explains how to configure and use the service.

well,
have to be written :-)

You'll need to install the following scripts  :
(and don't forget to make them executable :-) with chmod a+x [filename] )
/etc/hotplug/input.agent
/etc/hotplug/input.rc
/etc/init.d/ruby_init

and the configuration file:
/etc/sysconfig/ruby.conf

edit the configuration file to adjust it to your system configuration

start the service and check if everything is done as requested and configured
/etc/init.d/ruby_init start

if everything is OK activate the service by running "chkconfig --add ruby_init" .

"chkconfig --list ruby_init" will tell you in which runlevels the service is active
 
root@svetljo SRPMS]# chkconfig --list ruby_init
ruby_init       0:off   1:off   2:on    3:on    4:on    5:on    6:off

you can deactivate it by running "chkconfig --del ruby_init"

The input configuration uses the same syntax 
as kbd.conf, mouse.conf, event.conf as explained
in the section about hotplug with input agent.

The other configurable options are:

HACK_VIDEO_ENABLE=no

If set to "yes", turns on at boot the hackvideo feature of the Backstreet Ruby kernel.
In case XFree PrefBusID is used set to "no"

HOTPLUG_RC_input=yes

If set to "yes", runs /etc/hotplug/input.rc to configure input devices which were activated
by the kernel before hotplug was available (drivers statically linked in the kernel).
Generaly needed by all systems unless you have all input drivers configured as loadable modules
and load the drivers after hotplug is accessible to the kernel.

AUTO_DM=no
AUTO_XFree=no

No description yet. Or may be ...
enables/disables the features explained in sections  
"7.3. 1st X server configuration file" and "7.4. Number X servers started by Display managers"
you don't need to modify your init scripts if you use the ruby_init service and enable them
in ruby.conf.

LOAD_MODULES=yes

if set to "yes" loads certain input device drivers in case a ruby kernel is running.

#
# input modules configuration
#
# module arguments

The list of modules which should be loaded in case ruby kernel is running and 
LOAD_MODULES is set to "yes". 
In the example file are listed all important input drivers (keyboards & mice).
If you have some of them compiled in the kernel, you may disable the loading 
of the corresponding drivers by commenting them out. 

the ext-status argument can give you detailed information about the current 
configuration, and valuable information in case you are in trouble.