how to use direct access token provided by twitter to MGTwitterEngine classes

[app2011]

hello every one !!
i am trying to integrate twitter in my native application . I submitted my application at https://dev.twitter.com/. I am using MGTwitterEngine (api) to post update on twitter wall. I have some sample application and get successfully logged in but as i am not xAuth authenticated user, twitter suggested me to set upone-time OAuth workflow to obtain the access token for a single account. Now my question is where i should provide access token and access token secret in MGTwitterEngine classes ? Its not appropriate question to ask but there are too many classes in MGTwitterEngine classes, i cant check the flow of each and every class. If somebody implemented??