PF Configuration - FreeBSD Release 9.0 x64

[Shiv. Nath]

I would actually question why avahi is even enabled on a server; perhaps 
the correct answer is simply to disable it in rc.conf.
>> You do know that avahi-daemon's main use is to advertise _services_running on a host?
>>
> Yes, but zeroconf-style services are often more of a peer-to-peer nature
> instead of fixed (which don't *need* zeroconf).  It's also a larger attack
> surface.
>
Dear Brandon A & Kimmo P.

Thanks for the kind assistance and advices, in my case disabling "avahi" 
would not effect me much because it is only a mail server. thanks once 
again.