I'm not so sure about the issue of incentives. I don't believe I understand enough to say anything around specific incentives.
I certainly know that from talking and working with a number of organizations specializing in working with people with disabilities that there is a tremendous amount of information and education available to employers, which they may not be aware of. If more employers were aware of the information and the assistance—which can be everything from design assistance through to knowledge of different types of software applications that can be brought into the workplace—this would be an extremely important first step.