Sharing an instance in my LAN network

Hi, I have 2 computers in my LAN both using Microsoft SQL Server 2005, now on one of them, there are 2 databases running and I want to have the other computer connect to the same instance so it can administrate the 2 databases also, but I just can't figure out how.. with anything I try it says "the user is not entrusted with a SQL connection"

Any help is welcome, i'm just a beginner so I might be wanting something that's not even possible.. it's a game server i'm running and it's pre-configured to only work with 1 login. It actually works fine on one computer, but infact only for 50%. And that's why I need another computer that connects to the same databases so I can run the server application twice.

You can register both server in Management Studio in one machine with proper sa password and manage them.