X10 and Halogen Lights

[kerflop]

I am in the process of building my home theater.  I am installing six can lights in the ceiling and using halogen bulbs in those cans.  I want to be able to dim, turn on and turn off those six lights using X10.  The lights will be on a 3way switch (one at the top of the stairs and one at the bottom)... 

What should I do to ensure that this works?  What switch should I order?

Thanks