The software for your Handspring (Palm) will not work in the PocketPC world. Check out Tube,
http://www.visualit.co.uk/tube.htm . The maps can be a little slow to load, but they sure are purty. They allow very easy scrolling and have routing feature too. Alternately and cheaply ;), you can usually find the subway maps you want on the web, save them as jpeg's, send hem o your Ax and view them with picture viewer. Not nearly as elegant as Tube, but functional.