yahoo dns and a records

Hello,
I've got a friend with four domains that he's trying to host on his box. This part is working, the problem is with yahoo dns. I don't have the username/pw at this time so i'm going on what i've been told, and from what i've gleamed through dig, but yahoo's dns is handling requests and is not resoolving the a record to my friend's IP. I am not sure how to change this. More info to follow, when i get it, but if someone could tell me exactly where to go on yahoo to get this working, a record pointing i'd appreciate it.
Thanks.
Dave.