Geoserver does not recognize SVG validated using XMLSpy

An SLD for point features which validates against the OGC schemas using XMLSpy 5.4 will not work with Geoserver. Line and Polygon styles work fine. An extract of the SLD is below. The difficulty appears to be in the case of the element WellKnownName, which in examples on the Geoserver distribution (funkypolyshp.sld) is given as wellknownshape. For OGC compliance the latter is incorrect.

<?xml version="1.0" encoding="UTF-8"?>
<!-- edited with XMLSPY v5 rel. 4 U (http://www.xmlspy.com) by A Paul R Cooper (British Antarctic Survey) -->
<StyledLayerDescriptor xmlns="http://www.opengis.net/sld" xmlns:ogc="http://www.opengis.net/ogc" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.opengis.net/sld
C:\WEBSER~1\SLDSCH~1\StyledLayerDescriptor.xsd" version="1.0.0">
<!-- a named layer is the basic building block of an sld document -->
<NamedLayer>
<Name>Elevation styles</Name>
<!-- with in a layer you have Named Styles -->
<UserStyle>
<!-- again they have names, titles and abstracts -->
<Name>elevations</Name>
<Title>ADD elevation point symbols SLD</Title>
<Abstract>Provides a symbolization for ADD feature codes</Abstract>
<!-- FeatureTypeStyles describe how to render different features -->
<FeatureTypeStyle>
<FeatureTypeName>feature</FeatureTypeName>
<Rule>
<Name>Elevation on Rock (Levelling or Trigonometric)</Name>
<Title>Elevation on Rock (Levelling or Trigonometric)</Title>
<ogc:Filter>
<ogc:PropertyIsEqualTo>
<ogc:PropertyName>elv00typ</ogc:PropertyName>
<ogc:Literal>24010</ogc:Literal>
</ogc:PropertyIsEqualTo>
</ogc:Filter>
<PointSymbolizer>
<Graphic>
<Mark>
<WellKnownName>circle</WellKnownName>
<Fill>
<CssParameter name="fill">#000000</CssParameter>
</Fill>
</Mark>
<Size>2</Size>
</Graphic>
</PointSymbolizer>
</Rule>
<Rule>
<ElseFilter/>
<PointSymbolizer>
<Graphic>
<Mark>
<WellKnownName>triangle</WellKnownName>
<Fill>
<CssParameter name="fill">#ff0000</CssParameter>
</Fill>
</Mark>
</Graphic>
</PointSymbolizer>
</Rule>
</FeatureTypeStyle>
</UserStyle>
</NamedLayer>
</StyledLayerDescriptor>