android facebook logout issues

android facebook logout issues

I have implemeted code for facebook connection to post message on wall ,
refere from this link https://github.com/facebook/facebook-android-sdk ...
every thing is working fine...
Now my issues is when I do logout() it is showing me logout successfully ...
private void clearCredentials() {
try {
facebookConnector.getFacebook().logout(getApplicationContext());
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
but when next time open an app ... it is not logged out.... Thanks in
advance...