I just found something that seems to answer this question .. it is a post on apachelabs.org and I am putting it here because I think it has relevant info to this problem
What I don't understand:
http://www.ebay.com/
My server is www.yoursite.com. How can a request for another site be
made on mine? What does it mean when I see something of this nature?
Somebody is trying to use your server as a proxy server. Check your
httpd.conf to make sure that the proxy is turned off. Most likely, they are
not being sucessful. To check for sure, you can do the following:
telnet www.yoursite.com 80
GET http://www.ebay.com/ HTTP/1.1
Host: www.ebay.com
and press "enter" twice at the end.
If you get your own homepage back, then everything is configured correctly
and apache is ignoring the attempt to use your server as a proxy. If you
get ebay's home page, then you are running an open proxy, which could be
dangerous.
Joshua.
Thanks Joshua