Java web-consumer in Domino and cookie session

Recently I've faced with few mistake that drain hours from me. I had to make integration with web-serivce. I imported WSDL file and got java classes generated, than I according to documentation I checked connect method with credentials...

Error connecting to 'endpoint' on port '443', SSL invalid certificate, may need to cross-certify

Spend some time and found very detailed answer on stackoverflow: Create cross certificate for Domino Java agent?

Tried connect method again - it worked! Gonna be easy task now (I thought). However nothing else except connect method worked. All other method of consumer either did nothing or returned null to me. I was confused, spend few hours and than contacted web-service provider, they were not familiar with Java and provided me example in PHP that worked as expected.

My issue was I had to set SESSION_MAINTAIN_PROPERTY to true for my proxy object.

 SecretServiceLocator service = new SecretServiceLocator();  
 SecretPortType port = service.getSecretPort();  
 ((javax.xml.rpc.Stub)port)._setProperty(javax.xml.rpc.Stub.SESSION_MAINTAIN_PROPERTY, Boolean.TRUE);  

SESSION_MAINTAIN_PROPERTY

Standard property: This boolean property is used by a service client to indicate whether or not it wants to participate in a session with a service endpoint. If this property is set to true, the service client indicates that it wants the session to be maintained. If set to false, the session is not maintained. The default value for this property is false.

Once I set session maintain to true - everything started to work.