file upload with scriptaculous and code igniter?

[eluser]edwardmolasses[/eluser]
hi everyone,

I was wondering if anyone was able to do file uploads with code igniter and scriptaculous?

I have the following scriptaculous/js code that executes when someone clicks the file upload button:

Code:

new Ajax.Updater('addImagesDiv', '<?=site_url()?>/weddings/ajaxAddImage/<?=$this->db_session->userdata('id')?>', {method:'post', asynchronous:true, evalScripts:true, parameters:Form.serialize('f1')});

where f1 is the form name and the file input looks like:

Code:

<input class="inputClass" type="file" name="userfile">

And in my controller ajax function ajaxAddImage, I do the traditional code igniter upload, but it doesn't upload the file and i get the error:

Unable to find a post variable called userfile.

Does anyone have any tips?

thanks,
andrew.