Question: 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 stays for a couple of seconds and vanishes. i have tested it in the emulator 2.2 and it works fine. 

what could be the possible reason of the behavior and how can i overcome it?

just found out that it happens when i am logged into facebook in another application. 
however in applications like photoshop express there is no such issue.

Just what am i missing??

Answer: 
I had the same issue. It was because I was connected with the official Facebook application. I disconnect from the official Facebook application and then I was able to launch the login dialog. The problem is with SSO.

I solved it by forcing the login dialog rather than SSO by passing FORCE\_DIALOG\_AUTH in the authorize methods in Facebook.java.
I got this FacebookException because of [developers site](https://developers.facebook.com/) was not working.After developer facebook site worked, this issue was resolved.