Registering a .biz

[Soheil Shaghaghi]

Hi everyone,
I am running bind 8 on a FreeBSD.
I usually register and host .com .net and .org domains.
Today one of my clients asked me to host a .biz and a .co.uk for him
I tried to setup the name server, but after setting up, I can't ping to any
of the 2 domains.
Am I doing something wrong?
Or do I have to do something special to get these working?

Thanks so much,
Soheil