Net::ICQ2000

I wrote something like:

#!/usr/bin/perl -w
use strict;
require 'ICQ2000_Easy.pm';

my $icq=Net::ICQ2000_Easy->new($uin, $password, "1");
$icq->Auto_Ack_Offline_Messages(1);
$icq->Set_Debugging(0);
$icq->Execute_Once();
$icq->Connected() or die "Error";
my $details;
$details->{Text}="This is my Message";
$details->{Target_UIN}=$target_uin;
$icq->Send_Command("Cmd_Mes_Send", $details);
exit 1;

but nothing happens. What is wrong here?
I got no error messages and no warnings...