registering name servers?

[Blake, Todd]

2 questions:

I registered a domain(let's call it test.org), but it seems register.com won't let my machine here at home(on a cable modem) be registered as it's DNS server, any idea why?  I e-mailed register.com asking them as well.

I then signed up to use www.secondary.com as a secondary DNS service,  and they now do zone transfers from me
so I listed their name servers as my name servers in register.com.  I have NS records in my zones files for my machine and their machines so whe you use dig, nslookup, host, etc.. they show the nameservers as the secondary.com nameservers and mine, but whois only shows their DNS servers.  My 2nd question is what kind if implications this would have.