in src/main/java/org/apache/sling/auth/oauth_client/impl/OAuthCallbackServlet.java [81:89]
static String getCallbackUri(HttpServletRequest request) {
String portFragment = "";
boolean isNonDefaultHttpPort = request.getScheme().equals("http") && request.getServerPort() != 80;
boolean isNonDefaultHttpsPort = request.getScheme().equals("https") && request.getServerPort() != 443;
if ( isNonDefaultHttpPort || isNonDefaultHttpsPort )
portFragment = ":" + request.getServerPort();
return request.getScheme() + "://" + request.getServerName() + portFragment + PATH;
}