Since you left the chat, I tried to submit a SADX stat. I had this one once:
The proxy server received an invalid response from an upstream server.
The proxy server could not handle the request POST /submit/stats/confirm.
Reason: Error reading from remote server
Apache Server at www.soniccenter.org
Then I got something that had no error code that said:
Access Denied! Your address is blacklisted. More information about this error may be available in the server error log.