If the D5000 doesn't have "commander mode" for wireless flash control, you can get the SU-800 commander. My D2X doesn't have a pop-up flash so I use this when I want to operate several speedlights wirelessly off-camera.I'm kind of wishing the D5000 had CLS (wireless flash) control.
It is pretty sweet! Now I just have to learn how to use it
I'm kind of wishing the D5000 had CLS (wireless flash) control.