[luau] DNS

[Randall Oshita]

@      IN      SOA   ns.joe.com. root.foo.com. (
               2003080800 ; serial number
               5m         ; refresh =  5 minutes 
               15M        ; update retry = 15 minutes
               3W12h      ; expiry = 3 weeks + 12 hours
               5h20M      ; minimum = 5 hours + 20 minutes

Using the example above they use a "@" for the zone (in front of IN).
Will this work for an internal network? I thought it had to be something
like foo.com.? Like so:
Foo.com.       IN      SOA   ns.joe.com. root.foo.com. (
               2003080800 ; serial number
               5m         ; refresh =  5 minutes 
               15M        ; update retry = 15 minutes
               3W12h      ; expiry = 3 weeks + 12 hours
               5h20M      ; minimum = 5 hours + 20 minutes
Because I seen a master zone file that used the "@" and it works - it
was for an external network though.
Any ideas?
Can anyone send me a copy of their master internal zone file?
Thanks
Randall