A version that works with with the newest savon version

gistfile1.rb

# Old version is here
# https://gist.github.com/657153

# In Gemfile
gem 'savon', :git => 'http://github.com/rubiii/savon.git', :branch => 'eight'
gem 'httpclient'

# Run this in the console to fetch the name and address of the first debtor
HTTPI::Adapter.use = :net_http
client = Savon::Client.new do
  wsdl.document = "https://www.e-conomic.com/secure/api1/EconomicWebservice.asmx?WSDL"
end

# Authenticate
response = client.request :n1, :connect do
  soap.body = { 
                'n1:agreementNumber' => 123456,
                'n1:userName' => 'api',
                'n1:password' => 'verysecret', 
                :order! => ['n1:agreementNumber', 'n1:userName', 'n1:password']
              }
end
# Save the session cookie
client.http.headers["Cookie"] = response.http.headers["set-cookie"].first

# Get the list of debtors
response = client.request :debtor_get_all 

# Get the name and the address of the first debtor
first_debtor_number = response.to_hash[:debtor_get_all_response][:debtor_get_all_result][:debtor_handle].first[:number]
response = client.request :n1, :debtor_get_data do
  soap.body = {
    'n1:entityHandle' => {
      'n1:Number' => first_debtor_number
    }
  }
end

# Convert the result to a struct for easier access
k,v = response.to_hash[:debtor_get_data_response][:debtor_get_data_result].to_a.transpose
s = Struct.new(*k).new(*v)

# And print it
puts s.name
puts s.address