Logging in to netbios server

I've just purchased a new laptop, running Vista. Had a 'bear' of a time
getting Vista configured appropriately to recognize my network. Now that I've
accomplished that, I can't seem to 'log in' to my main file server. This
server was built by my step son and is running FreeBSD. It works
wonderfully.........but the login prompt requires 'only' a user name and
password. Unfortunately, Vista seems to add the machine name
'AcerLaptop/username'......which makes my login attempt invalid. Can anyone
tell me how to tweak Vista to 'remove' that machine name from the login
dialog?