Can not follow code in LWP

My code open a socket and talk HTTP/1.1 to a remote web server, but I
notice extra characters in the response, so I use lwp-download
http://www.genius.com/index.html and capture the response with a
packet analyzer (ethereal).  The packet analyzer show 1ff8 after the
response header and a 0 at the end of the response.  When I look at
the downloaded file, these characters are not there.

I tried this with another web server http://www.webex.com/index.html,
and see the same symptoms.  Any idea what these characters are and
what lwp-download does with them?

Thanks
Khai