[Asterisk-Users] Multiple Realm Definitions?

[S McGowan]

Hate to keep asking, but I've not been able to find it covered online or in
docs. 

I know you can define multiple domains in the sip.conf, but can you define
multiple realms?

For instance, I use a central server that handles a couple of area codes, and I
would like to be able to have authentication realms such as
<areacode>.hostname.domain.

Anyone?