I'm trying to force my formpanel to upload a file together with the rest of the form data. I'm fighting with this a whole day. I searched the forum and tried lot of code. Still I get $_FILES empty on the server side... Please, help! Here is my code:

[CODE]
var zaliczki = new Ext.FormPanel({
labelAlign: 'top',
frame: false,
title: 'Zaliczki',
bodyStyle:'padding:5px',
width: 600,
items: [
{
xtype:'tabpanel',
deferredRender:false,
enableTabScroll:true,
id:'taby',
activeTab: 0,
defaults:{autoHeight:true, bodyStyle:'padding:10px', autoScroll:true},
items:[
{
title:'Transza 1',
layout:'form',
defaultType: 'textfield',
items: [


{
xtype:'tabpanel',
deferredRender:false,
enableTabScroll:true,
id:'taby2',
activeTab: 0,
defaults:{autoHeight:true, bodyStyle:'padding:10px', autoScroll:true},
items:[
{
title:'Zaliczka',
layout:'form',
defaultType: 'textfield',
items: [
{
fieldLabel: 'Kwota zaliczki (w PLN)',
name: 'data[{{$smarty.section.dane.index}}][zal_kwota]',
value: '{{$dane[dane].zal_kwota}}'
},
{
fieldLabel: 'Procent w stosunku do kwoty wsp