I have implemented FB in my application an it is working perfectly in my samsung device o/s 1.5. However in the HTC Evo the FB login dialog disappears soon after loading. it
The issue is actually that you haven't set up your Key Hash for your application with Facebook yet which is required to use SSO. FORCE_DIALOG_AUTH actually disables SSO, but this is a poorer user experience. Instead, take a look at an article I put together after struggling with this issue which describes the correct way to tackle your problem:
http://sean.lyn.ch/2011/07/android-the-facebook-sdk-sso-and-you/