Prova - I'm using Images Plus Camera Control to successfully run both my Nikon D40 and Canon 350D.
I run a serial cable to control the 350D's bulb function, and am going to get the Shoestring astronomy infrared adapter to control the Nikon's bulb release as the Nikon doesn't use a hardware cable solution.
Other than for bulb release, Images Plus CC runs both cameras main functions, including focus control, just the same through their standard USB cables.