bingbing - 11:43 am on Sep 28, 2012 (gmt 0)

Exactly, this is what we are trying to ascertain. Bing crawls websites to build an index. If the URLs are not in the website, how can it find URLs and also post valid CGI parameters to them? We've changed that URL twice now, so that proves there is no link to the URL, otherwise we'd need to have changed the offending link too (and we did not).