How can I set an option using a callback? I want to dynamically add some buttons to my dialog and set the height, but jquery seems to completely ignore my function(). How is this done correctly?

 <span id='dialog1'>Bewerken</span>
 <script type='text/javascript'>
 $(document).ready(function() {
 $('#dialog1').click(function() { 
 $('<div></div>')
 .attr('title', 'Monster')
 .dialog({'buttons': function() { return {'Ok': function() { alert('hoi'); } } },'height': function() { return $(window).innerHeight(); },'modal': '1','width': '800'})
 .dialog('open')
 .css({'text-align': 'center'})
 .append( $('<img />').attr('src', '/images/loading.gif') )
 .load('http://sitwst05-panta/worksheet/resultaten_invoeren.php?worksheet_id=416&monster_id=4536&single=1')
 ;
 return false;
 });
 });
 </script>