The best approach I have found when applying to a company is to discuss this expectation up front on the second interview. To discuss this as a going in position will only leave your perspective manager with a question about is this person really a team player and does he really want to work here. We all know that IT means it is not an 8 hour and day, 5 day a week type job and if you do not know this them being in IT is not for you.

I have over the years struggled with this fact as my wife is not an IT person but does very well in exceeding here employers’ expectation during her time at the office but does not believe in overtime under any circumstances. This of course was a very big issue for a long time but she has finally excepted that it is a big part of my life as an administrator and former programmer that it is now an unspoken law that my laptop will go with me on vacation with no exception and no discussion.

As far as addtitional compensation, it is something you really need to nail down in the begining and make sure you hold your employer to his/her word especially when it comes to comp time.