WFS DWITHIN filter not work on arcgis 9.3

[PhilScadden]

If post the following query to arcgis

<wfs:GetFeature xmlns:wfs="http://www.opengis.net/wfs" service="WFS" version="1.1.0" xsi:schemaLocation="http://www.opengis.net/wfs http://schemas.opengis.net/wfs/1.1.0/wfs.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><wfs:Query typeName="Petroleum_wells" srsName="EPSG:102113"><ogc:Filter xmlns:ogc="http://www.opengis.net/ogc"><ogc:DWithin><ogc:PropertyName>SHAPE</ogc:PropertyName><gml:Point xmlns:gml="http://www.opengis.net/gml" srsName="EPSG:102113"><gml:pos>19386414.338657 -4738138.3627612</gml:pos></gml:Point><ogc:Distance units="meter">0.15605383691906002</ogc:Distance></ogc:DWithin></ogc:Filter></wfs:Query></wfs:GetFeature>

I get back:
<ows:ExceptionReport version='1.1.0' language='en' xmlns:ows='http://www.opengis.net/ows'><ows:Exception exceptionCode='InvalidParameterValue'><ows:ExceptionText>The spatial operation is invalid (invalid name or namespace for distance element).</ows:ExceptionText></ows:Exception></ows:ExceptionReport>

Same request works on other WFS servers. I've tried different distance units, no go. What have I missed here?

[PhilScadden]

Whoops. On closer inspection of WFSCapabilities, ArcGIS doesnt even support DWITHIN.