gistfile1.rb

require 'rubygems'
require 'pp'
require 'json'
require 'httparty'

url = "http://www.adgonline.de/adg_online/phoenix/searchalyzr.jspx"

class Loader
  include HTTParty
end

json_params = {"categoryStates" => [], 
              "columns" => [],
                'searchQuery' => {"parameterAssignments"=> [], 
                                 "terms"=> ["Manag"], 
                                 "limit"=> 10}, 
                "vrbSessionId"=> {"sid"=> "", "uid"=> ""}}

headers = {'X-RequestedWith' => 'XmlHttpRequest'}

query = {'aktion' => 'getSearchResult',
         'searchParams' => json_params.to_json,
         'searchSystemType' => 'ionas3_adg',
         'searchSystemUrl' => '_:'} 

result = Loader.post(url, :query => query, :headers => headers)

puts result.body

# what's wrong with the json?
data = JSON.parse(result.body)