Can I pass values over a bitcoin bip 70 URI? is it possible to add arguments such as BTC amount to a bip 70 URI, something like:

bitcoin:?r=http://127.0.0.1:8000/paymentobject/?amount=10


I already tried with the backwards compatible URI:

bitcoin:?amount=10&amp;r=http://127.0.0.1:8000/paymentobject/


But the client doesnt seem to register anything other than the 'r=' param.

Any help greatly appreciated :)



EDIT:
Added function from django views.py for extra explenation-

def protoresponse(request):
    xpo = payments_pb2.ParseFromString(request)

    returnaddress = xpo.Payment.refund_to
    transactions = xpo.transactions
    memo = xpo.Payment.memo

    xpa = payments_pb2.PaymentACK
    xpa.payment = xpo.SerializeToString()
    xpa.memo = u'success, i think'
    return HttpResponse(xpa.SerializeToString(), content_type="application/octet-stream")


Note, the function is defined as protoresponse because we have optional string payment_url = 6; in the payments.proto file.
The purpose of the BIP70 is to provide a secondary URL, which, when visited by your client wallet, will provide all the details to make the transaction, and a whole lot more. It was designed to be linked to POS systems which would generate the information and produce a unique URL.

In the standard Bitcoin URI scheme, it is possible to pass the amount, but you also need to pass the pay-to address.