nginx 301 redirect loop

I have recently switched one of our high-traffic sites from Apache to nginx.

On a few of the posts I get this 301 redirect loop. For example, this page gives the loop:

https://www.storyofstuff.org/2012/01/29/compost/

But if you add a ? at the end the post loads fine:

https://www.storyofstuff.org/2012/01/29/compost/?

Other posts on the blog load fine, for example:

https://www.storyofstuff.org/2012/01/29/concentrated-packaging/

I followed the configuration to the letter here and have tried using the WP-nginx plugin. The only difference is I included the SSL directives.

Looking at the headers send using curl I get the following:

user@host ~ $ curl -i https://www.storyofstuff.org/2012/01/29/compost/
HTTP/1.1 301 Moved Permanently
Server: nginx
Date: Mon, 05 Mar 2012 18:27:20 GMT
Content-Type: text/html; charset="UTF-8"
Transfer-Encoding: chunked
Connection: keep-alive
X-Powered-By: PHP/5.3.10
Vary: Cookie
Location: /2011/01/29/compost/

user@host ~ $ curl -i https://www.storyofstuff.org/2011/01/29/compost/
HTTP/1.1 301 Moved Permanently
Server: nginx
Date: Mon, 05 Mar 2012 18:27:33 GMT
Content-Type: text/html; charset="UTF-8"
Transfer-Encoding: chunked
Connection: keep-alive
X-Powered-By: PHP/5.3.10
Vary: Cookie
Location: /2012/01/29/compost/

user@host ~ $

Could it be an issue with the database?

Thank you in advance.