Draw a simple 3D line in CS4 action script

I have a number of sphere’s which have random x, y and z values.
I thought it would now be simple to create a vector with the x,y,z coordinates on the spheres I want to connect and that would be that.

However the vectors remain in the 2D plain.

I have been searching for simple example of how to do this without success and realise I am doing something quite dumb but if someone could help me out, it would be appreciated.