You said your code reports the following error:

HTTP/1.1 407 (Proxy Authentication Required) Proxy Access Denied
   # stuff we don't need to know deleted.
   Proxy-Authenticate: NTLM 
   Proxy-Authenticate: Basic realm="..."
   Client-Warning: Unsupported authentication scheme 'ntlm'
[download]

The error message suggests you need to provide a username and password to the proxy server. Borrowing heavily from lwpcook, something like this might be in order:

   use LWP::UserAgent; 
   $ua = new LWP::UserAgent;
   $ua->proxy(http => 'http://proxy.example.com:80'); 
   $ua->proxy_authorization_basic( 'username', 'password' );
   my $req = new HTTP::Request ('GET', 'http://www.yahoo.com/'); 
   $page = $ua->request($req)->as_string; 
   print $page;
[download]

For what it's worth, this search provides a number of links to messages with a variety of related (and unrelated) information on the subject.

Also, it would help if you checked out some of these links, which will help you understand the best way to use the Monastery:

• Writeup Formatting Tips
• Before You Post ...
• On asking for help
• PerlMonks Commandments (was: Seven Deadly Sins)
• Newbie Monk Seeking Enlightenment

--f