add realm based on NAS-IP

[Alan DeKok]

On Jul 8, 2016, at 5:00 AM, tirili at web.de wrote:
> 
>   I got a step further. I have to modify hints for := instead of =

  Yes, this is documented.

>   But if s.b. I want to have a check if @ is contained in username, I get
>   a reject???

  Regular expressions are not supported in the "hints" file.

  Use unlang statements.  They are *much* better.

  Alan DeKok.