Joining Ball screws

I have a number of Star Ball screws with a shaft diameter of around 1
inch which I pulled off a machine in a salvage yard.
Very similar to this ball screw on ebay:
http://cgi.ebay.com/ws/eBayISAPI.dll?
ViewItem&item=2563414108&category=1267

Unfortunately their shaft lengths are too short for my purpose.

Someone suggested to me that you can have the screws cut and joined
together.

Although probably not desirable, is this actually possible?

Thanks
Robert