Aegis Industrial Softwares CircuitCAM can import a gerber file, and allow you to establish a pick and place program from it. It can also take a scanned image of the actual board to do this. It's a moderately painful process; but it is doable.
CircuitCAM also takes in CAD ASCII files, to help with creating a pick and place program. The ASCII input method is much easier and faster than the gerber input method. Most CAD files can output an ASCII file with all of the data you need.
I receive no incentives from CircuitCAM, though I am a happy customer.