History of the issue can be followed there:
Summary: the SOAP server does not generate a detailled phpdoc for arrays. And so it does not generate generate a WSDL with fully detailled arrays. Arrays need to be fully detailled in the WSDL in order to be JAVA compatible (from my understanding of SOAP with JAVA).
By fully detailled I mean the array content that could be objects, arrays or primitive type need to be described.
At this moment we could try to generate an detailled phpdoc for array but I'm not sure if it's possible. If it's not possible then the solution would to parse the description and generate the WSDL without using the Zend reflection that look to the generated phpdoc.
Also in this case we need to think if we prefer to have a new JAVA SOAP server and keep the current one or to change the current one.