Hello fellow developers(?) I'm running Apache SOAP 2.2 (not the nightly builds) and I'm having problem with the xsi:null attribute. I've found that xsi:null only works with the 99-xsi namespace. The problem is in the static method SoapEncUtils.isNull(Element element). Below is a quick fix I made to make this work with all namespaces for xsi. I have also included a new constant to make this method work with the Microsoft .Net Beta 2 who send xsi:null's as xsi:null="1". If this is allready fixed in the nightly builds please excuse this posting. cheers, -kims- org.apache.soap.encoding.soapenc.SoapEncUtils public static boolean isNull(Element element) { String nullValue = DOMUtils.getAttributeNS(element, Constants.NS_URI_1999_SCHEMA_XSI, Constants.ATTR_NULL); if( nullValue == null ) { nullValue = DOMUtils.getAttributeNS(element, Constants.NS_URI_2000_SCHEMA_XSI, Constants.ATTR_NULL); } if( nullValue == null ) { nullValue = DOMUtils.getAttributeNS(element, Constants.NS_URI_2001_SCHEMA_XSI, Constants.ATTR_NULL); } return (( nullValue != null ) && ( nullValue.equals(Constants.ATTRVAL_TRUE) || nullValue.equals(Constants.ATTRVAL_1))); } org.apache.soap.Constants public static String ATTRVAL_1 = "1";