hi,
well you have to modify the code. You can write your own authentication
class using sockets that will write the authentication details to your
company proxy..(obviously that would be running on some network port,
so you need to send and recieve data on that port using your socket in
your authenticaion class).

Now when you recieve first request in HTTPClient Class then instead of
forwarding it to the remote host directly, first you call your
authentication class using whatever credintials you provide, that class
will write the credentials to your company proxy and recieves the
response, once you get the resposne then you need to simply forward
that captured HTTP request to your company proxy. Instead of the remote
host address you need to initilize your remotehost in HTTPClient class
to the IP Address and port of your company proxy...rest it will handle
itself.....

hope this helps..