I also got a Cannot redeclare class OAuthServer error. It occurs because an other plugin had already loaded a version of this class.
I solved this by adding this construct around the OAuthServer and OAuthDataStore class in class.oauth.php:
if (!class_exists(‘OAuthServer’)) {
class OAuthServer {
….
} // end of class
} // end if OauthServer
f (!class_exists(‘OAuthDataStore’)) {
class OAuthDataStore {
….
} // end of class
} // end if OAuthDataStore
Could this be added to the comming release?