The definition types are controlled by the license that you are using with the product. A trial license would have everything enabled until the trial ran out. Did your trial license run out or are you using a different license? Either way you may want to contact your sales rep or support and get a new trial license and then Macintosh will show up in the list.
I had trouble activating the standard 45-day evaluation license and had to work with a support representative to get things working... There's probably something not included in the license I'm using. I've contacted that support representative again and hopefully we'll be able to get that resolved.
Thanks for pointing me in the right direction.