Chyba, nevím ale v čem

<script type="text/javascript">

<!--

default_width = 640;

default_height = 480;

getElementById('main_image').style.width = default_width+"px";

getElementById('main_image').style.height = default_height+"px";

/*zoom_positions = array(0.25, 0.5, 1, 1.5, 2, 4, 8);*/

document.write(1); //tohle se nyvypíše, z toho soudím, že chyba je na 3. nebo 4. řádku

function zoom_plus()

{

 /*global default_width;

 global default_height;*/

 getElementById('zoom_plus').src = 'skins/icons/zoom_plus2.gif';

}

function zoom_minus()

{

 /*global default_width;

 global default_height;*/

 zoom_minus.src = 'skins/default/zoom_minus2.gif';

}

function zoom_default()

{

 /*global default_width;

 global default_height;*/

 zoom_default.src = 'skins/default/zoom_default2.gif';

 main_image.style.width = default_width;

 main_image.style.height = default_height;

}

document.write(2);

//-->

</script>