How to create "cachedXAuthAccessTokenKey" using XAuthTwitterEngine in Twitter in iphone

Question

Hi,

I am working on login page validation for twitter application. I have downloaded the sample code of "XAuthTwitterEngineDemo". Now i have created kOAuthConsumerKey and kOAuthConsumerSecret keys and implemented in my code. But i donno, how to create "cachedXAuthAccessTokenKey".

   #define kCachedXAuthAccessTokenStringKey @"cachedXAuthAccessTokenKey"

Is need to create that key?. If yes, Please guide me to how to create?. If i run that program, i entered the correct user name and pass word into the text fields, it shown the message as Incorrect user name/Pass word. I donno why its happened?. so please guide me.

Thanks.