i'd just like to point out that when the cookie_jar in LWP::UserAgent is used in this manner, it will automatically grab and store the cookies from all HTTP::Responses returned by the UserAgent. it will also automatically add cookies to all HTTP::Request objects that pass through it.

so, if you set a UserAgent's cookie jar, there is typically no need to manipulate the cookie jar manually (i.e. with extract_cookies and add_cookie_header).