I use an Android WebView for Twitter OAuth: Twitter asks the user to log in and authorize the application, I retrieve the access token and persist it in my application.
Don't clear cookies beacause it will effect other sessions like facebook etc.. stored inside the cookie so try to follow this method
Before oauth transaction such as before the webview creation
CookieManager cookieManager = CookieManager.getInstance();
cookieManager.setAcceptCookie(false);
After oauth transaction let accept cookie by setting
cookieManager.setAcceptCookie(true);
it will work i have tested it..