Call Webservice from AJAX using XMLDocument as inparameter?

Is it possible to call a webservice form AJAX, when the webservice takes and XMLDocument as in parameter? And if so how?

I'm trying to call the webservice with the following javascript code:

SearchAddress.TestWebservice.SearchEBMS(searchXmlD oc, OnEBMSComplete, OnEBMSError);

Where searchXMLDoc was created using the ActiveXObject("Microsoft.XMLDOM"); method i ie. The call works fine when changing the webservice in paramater to a simple string, but I want to send XMLDocument to it instead, but it seems not to work?
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