Suitelet iframed in Portlet

Having failed at getting client side script libraries to work in a portlet I am now trying to create a suitelet and iframe it in a portlet as a work around. If I view this suitlet the select works properly and I am able to show the value on post.

If I view this suitelet in an iframe in a portet the select does not work at all. You can view it but it doesn't drop down.

Can anyone see anything wrong in my code?

 function projectMap(request, response) {    var form = nlapiCreateForm('Customer Map', true);     var select = form.addField('selectfield', 'select', 'Select');   select.addSelectOption('','');      select.addSelectOption('a', 'Prospects');      select.addSelectOption('b', 'Customers');      select.addSelectOption('c', 'Both');      select.addSelectOption('d', 'Customers no Go Live');                form.addSubmitButton('Go');           if(request.getMethod() == 'POST') {       var param = request.getParameter('selectfield');      var field = form.addField('lblparam', 'label', param);     }        response.writePage( form );      }