This is a good link for night weaning by Dr. Jay Gordon  http://drjaygordon.com/attachment/sleeppattern.html

You can start giving your baby a small cup with water to get the hang of drinking from a cup and then you will be able to give milk or other fluids once you are back at work.  My daughter does not take a bottle but she can drink from a cup pretty well now at 12 months.  She does like to dump the water once she has a drink, however :)