Parameter "xy" is not optional

Hi,

i have problems with running simple SOAP function using two clients:
 - standard PHP SOAP client
 - Python ZSI version 1.7

Result is the same in both cases:
UndefinedServiceMethod:
interface name: soap
service name: test
Parameter "first" is not optional

server
-------
from ladon.ladonizer import ladonize

class test(object):

 @ladonize(unicode,unicode,rtype=unicode)
 def test(self, first, second):
  return first

client Python
---------------
from ZSI.client import Binding
from ZSI import TC

bind = Binding(host="127.0.0.1", port=8080, url="/test/soap")
result = bind.RPC(None, "test", ("aaa", "bbb"), TC.Any(), requesttypecode=TC.Any("test"))

client PHP
------------
$sck = new SoapClient(null, array("location" => "http://127.0.0.1:8080/test/soap", "uri" => "http://127.0.0.1:8080/"));
$result = $sck->__soapCall("test", array("aaa", "bb"));

XML from python client
--------------------------
REQUEST:
<?xml version="1.0" encoding="utf-8"?>
<SOAP-ENV:Envelope
  xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"
  xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xmlns:xsd="http://www.w3.org/2001/XMLSchema"
  xmlns:ZSI="http://www.zolera.com/schemas/ZSI/"
  SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/" >
<SOAP-ENV:Body>
<test>
<element id="ob77fdf20" xsi:type="xsd:string">aaa</element>
<element id="ob77fdf38" xsi:type="xsd:string">bbb</element>
</test>
</SOAP-ENV:Body>
</SOAP-ENV:Envelope>

RESPONSE:
Date: Sat, 24 Sep 2011 14:10:18 GMT
Server: WSGIServer/0.1 Python/2.7.1+
Content-Type: text/plain; charset=utf-8
Content-Length: 775

Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/ladon-0.6.3-py2.7.egg/ladon/server/wsgi_application.py", line 355, in __call__
    response_part = dispatcher.dispatch_request(request_data,environ)
  File "/usr/local/lib/python2.7/dist-packages/ladon-0.6.3-py2.7.egg/ladon/server/dispatcher.py", line 157, in dispatch_request
    result = self.call_method(method,req_dict,tc,export_dict)
  File "/usr/local/lib/python2.7/dist-packages/ladon-0.6.3-py2.7.egg/ladon/server/dispatcher.py", line 50, in call_method
    raise UndefinedServiceMethod(self.iface._interface_name(),self.sinst.servicename,'Parameter "%s" is not optional' % arg['name'])
UndefinedServiceMethod:
interface name: soap
service name: test
Parameter "first" is not optional

Python 2.7.1
PHP 5.3.5

Any ideas ?

Thank you !