Intermittent HTTP 401 response for request token



Has anyone else encountered intermittent 401 responses when request an OAuth Request Token? We generally receive a 200 response with the request token but there are times when we will receive a 401 with the error message:
{"code":89,"message":"Invalid or expired token."}.

Per the OAuth 1 spec, I’d expect a 401 response for only a handful of conditions, but I’m having a difficult time identifying the root cause of the sporadic error responses.

We’re also seeing intermittent HTML error page responses when requesting an access token. The HTML page returned has the title Twitter / Error.

I should also note that our OAuth 1 code has not been modified recently.

Any insight on the topic would be greatly appreciated!