Looking for client configurations for dynamic client

[Fabián Omar Franzotti]

Hi guys
I'm running Debian lenny... in production server I have installed freeradius 1.x and in client.conf i have seted
client 0.0.0.0/0 {
    secret = mySecret
    shortname = everyone
}

In Debian lenny is available freeradius 2.0.4 in this version that setting for client is not available.
Some time ago Alan told me that use 2.0.5 version to this settings, I did try to build a .pkg to install in my server but never can 
done it, because i did have some errors and my knowledge are not enought.
Well I want to know if some one can tell me how i can have clients that don't have static IP's if I don't allow access to every 
world, because nas database is loaded only at startup time.
I think i can use dynDNS or something like that, so I can declare the host.name and not IP address, but I want to know if exists 
some way to handle this case. Ah the clientes can be added by it self with a register page.
Any Idea?

Thanks guys...
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Fabián Omar Franzotti
Resistencia - Chaco - Argentina
Tel Arg.: 54-(372)-243-8710 /  54-(372)-257-0347
USA Phone: 1-(321)-284-3865