my %vars = (
  from => $From_address,
  # assume multiple addressed are separated by comma
  to => join(',', @To_addresses), 
  cc => join(',', @Cc_addresses), 
  subject => $Subject,
  body => $Mail_body,
  # etc.
);

# and then invoke the PHP script via POST

# send the POST to php
my $url = "http://domain.com/test.php";
my $req = new HTTP::Request;
my $res = $us->post($url, \%vars);