How to access/parse an associative/hashed array as responce using mozilla's SOAP client in javascript from the SOAPPropertyBag?

I'm trying to parse/access an associative/hashed array from a soap
server. I can't find a way to retrieve/access/parse the returned
associative
array in Firefox 2.0 using JavaScript

after my call to the server...
var returnObject = soapcall.invoke();

the returned value (returnObject.getParameters(false, {})[0].value)
appears to be a SOAPPropertyBag but I can't find a way to get this
into a javascript associative array/object.

returnObject.getParameters(false, {})[0].element is a reference to the
returned soap xml responce. But the idea of using soap or any other
rpc method is that you don't have to walk the DOM tree yourself.

Any help is greatly appreciated,

Thank in advance

Jan Snelders