use LWP::UserAgent;
$ua = LWP::UserAgent->new;
$ENV{ http_proxy } ='http://localhost:80';
$ua->env_proxy;
print  $ua->get( 'http://www.google.com' )->as_string;

##</code><code>##

[Sat Jun 17 17:30:57 2006] [debug] proxy_http.c(630): Content-Type: text/html