A client application, during the initialization of the session (that happens inside a class that implements org.zkoss.zk.ui.util.SessionInit) requires data to another application via a web service and puts the data obtained in session variables. When the application attempts to assign these data to session variables is periodically generated an exception that is cyclically repeated endlessly until generate a StackOverflowError.

Will find attached the class that initializes the session and the exception thrown.