Sgt_Kickaxe - 9:36 pm on Sep 9, 2012 (gmt 0)
Wordpress - a general note about the popular CMS that may apply to others like drupal as well.
Wordpress does a lot of redirecting on your behalf. If, for example, a url is example.com/this-is-an-example-page and you visit any of these very similar urls you will likely end up on the same url
Now those are all different urls but wordpress takes a best guess that the page the visitor really wanted was - example.com/this-is-an-example-page and it sends the visitor there, via 301, MOST OF THE TIME.
You need to make sure that variations of your urls, that don't exist as real destinations, don't simply display the RIGHT content on the WRONG(not redirected) url. You DO NOT want to see "example.com/this-is-an-example-page" content on "example.com/this-is-an-example-page.." (for example, note the two trailing periods).
To test simply add a couple of periods to the end of a wordpress url and see how your installation handles it (it varies by host). Unfortunately there is no easy way to turn this wordpress feature off.