That's right Gregor. As long as the initial activation is done, if there's no internet connection you can either tell Steam to work offline or just go to the actual .exe for 09 in the Steam apps folder and load the game without Steam getting involved at all.
Not sure why the OP is having problems though - if you have the Steam download version, then you'd have needed internet for that anyways, and if it's the boxed version then you can install using the phone activation can't you?