Solved !
thanks for every help i had :)

Found http://stackoverflow.com/questions/8026524/how-do-i-force-lwp-to-use-cryptssleay-for-https-requests and solved my issue with

use Net::SSL (); # From Crypt-SSLeay
BEGIN {<br />
  $Net::HTTPS::SSL_SOCKET_CLASS = "Net::SSL"; # Force use of Net::SSL
  $ENV{HTTPS_PROXY} = 'http://10.0.3.1:3128';
}
[download]

------------------ Hi
I tried a thousand different ways to connect to the URL https://sis-t.redsys.es:25443/sis/entradaXMLEntidad/ and i seem unable to get something else than a 500 error.

Latest code i tried was

require LWP::UserAgent;
 
my $ua = LWP::UserAgent->new(ssl_opts => { verify_hostname => 0});
$ua->agent("Mozilla/8.0");
$ua->timeout(10);

my $req = HTTP::Request->new( GET => "https://sis-t.redsys.es:25443/si
+s/entradaXMLEntidad/");
$req->header( 'Accept' => 'text/html' );

# send request
my $res = $ua->request($req);

# check the outcome
if ( $res->is_success ) {
    print $res->decoded_content;
} else {
    print "Error: " . $res->status_line . "\n";
}
[download]

I tried with and withcout $ua->proxy('https', 'http://192.168.0.1:80');
I tried POST and GET (since in the end, ill have to access that URL with POST)

of course I made sure I was able to get this page from a regular browser. I made sure my code always was able to connect to other pages with the form of https://some-domain:some-port/path/to/another/page

If anyone can help me to find what i do wrong, I d be thankfull