Sharing login credentials on localhost with 2 web applications on IIS7, possible?

Question

I have 2 asp.net web applications running in IIS7:

http://app1.local/

and

http://app2.local/

My host.ini file just maps the above urls to localhost:

::1 app1.local
::1 app2.local

I added the same machine key to both their web.config's.

When I sign into app2, and then go to app1, the call to Request.IsAuthenticated is false?

Should this work?