AIR Runtime version comparison / updating

Question #1: Is there any built in function, that could compare AIR runtime versions. I know the current runtimeversion that the user has, and I know the version that I developed for. Now I would like to make sure that the user has the same or newer version of the runtime.

I can split the runtime version by the periods and compare each chunk seperatly, byt maybe there is some function in AIR that would handle it for me?

Question #2: How to update the air runtime? Should I air.navigateToUrl() the user to :http://www.adobe.com/go/EN_US-H-GET-AIR orhttp://get.adobe.com/air/?promoid=BUIGQ and quit the app?