Добавление переменных POST после инициализации SWFUPLOAD:
var form = document.adminForm;
if (form.catid.value == "0"){
alert( "<?php echo JText::_( 'You must select a category', true ); ?>" );
} else {
var radio = $('adminForm').value;
upload1.addPostParam("published" ,radio),
upload1.addPostParam("cat_id" , document.adminForm.catid.value );
upload1.addPostParam("MAX_FILE_SIZE" ,"5000000" );
upload1.addPostParam("UPLOAD_MAX_FILESIZE" ,"5000000" );
upload1.startUpload();
}
var upload1;
window.onload = function() {
upload1 = new SWFUpload({
post_params: {},
upload_url: "upload.php",
file_size_limit : "1024",
...
})