my website based on wordpress 2.8.4 have this problem
I use mod-rewrite, try to open some pages for sure randomly you will be redirected to a FEED comment page....never i saw a similar think.
I disabled all plugins, i reinstalled wordpress but the problem happen in any case.
In here you can check my PHP configuration:
As you will see i use PHP 5.3.0. Before write this post i did a test with PHP 5.2 but the problem is the same in any case....
If you are able please identify the problem because if i'm able to identify the problem i can try to call the Hosting online support.
Thanks in advance.