file upload with attachment_fu.

Right now i am uploading file in public folder..

This is my setting ...

This code is working fine ...

Class ClientDocument < NdsiActiveRecord

  has_attachment :storage => :file_system,
    :max_size => 20.megabytes

  def self.upload_client_document(params)
    client_document = self.create! :uploaded_data =>
params[:Filedata],:client_id => params[:client_id],:document_name =>
self.default_document_name,:document_description =>
self.default_description_name
    self.rename_document_name(params,client_document)
  end

end

class ClientDocumentsController < ApplicationController

def upload_document
    ClientDocument.upload_client_document(params)
end

Now i want to upload my files to specific url like ..

http://demo.test1.com/v12451/search.aspx?username=test1&password=test2

how may i do this with attachment_fu ??

And help or idea ??