Django ajax file upload to request.FILES - django

Question

I'm using Valumns File Uploader to load files to django. This supports an ajax upload via XHR for modern browsers and an iFrame fallback for older ones like IE.
Now the problem: If I upload large files, only iFrame upload works, because here the files are mapped into request.FILES and django writes them to the disk immediately instead of memory.
If XHR upload is used, I have to read request._raw_post_data and write this to disk, but it fails with an MemoryError.
This is my file uploader initialization:
var uploader = new qq.FileUploader({
'action': uploadUrl,
'multiple': true,
'allowedExtensions': allowedExtensions,
'element': selector,
'debug': true,
'onComplete': completeFunction,
'onProgress': progressFunction,
'onSubmit': submitFunction
});
At the django end I use the following code to write the file content to disk:
# open a new file to write the contents into
new_file_name = str(uuid.uuid4())
destination = open(upload_path + new_file_name, 'wb+')
# differentiate between xhr (Chrome, FF) and pseudo form uploads (IE)
if len(request.FILES) > 0: # IE
for chunk in request.FILES[0].chunks():
destination.write(chunk)
else: # others
destination.write(request._raw_post_data)
destination.close()
I also tried this solution from Alex Kuhl, but this fails with an IOError: request data read error.
Is there any way to get the files uploaded via XHR into request.FILES and so use the django builtin handling?