foreach my $req (@$reqs) {
    print "Registering '".$req->url."'\n";
    if ( my $res = $pua->register ($req) ) {
      print STDERR $res->error_as_HTML;
    }
  }
  $entries = $pua->wait();

  foreach (keys %$entries) {
    my $res = $entries->{$_}->response;
  }

##</code><code>##

undef %entries # or
%entries=();