When creating a stock ICE 2.0 EE GA - JSF 2 sample and adding the following param:

<context-param>
  <param-name>javax.faces.FACELETS_DECORATORS</param-name>
  <param-value>com.icesoft.facelets.HtmlTagDecorator</param-value>
</context-param>

I get see the following exception on startup:

org.w3c.dom.DOMException: INVALID_CHARACTER_ERR: An invalid or illegal XML character is specified.
at com.sun.org.apache.xerces.internal.dom.CoreDocumentImpl.createAttribute(CoreDocumentImpl.java:564)
at org.icefaces.impl.context.DOMResponseWriter.writeAttribute(DOMResponseWriter.java:256)
at com.icesoft.faces.impl.renderkit.xhtml.XhtmlRendererBase.encodeBegin(XhtmlRendererBase.java:42)
at javax.faces.component.UIComponentBase.encodeBegin(UIComponentBase.java:824)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1641)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1646)
at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:389)

The exception is thrown from the following line of ICEfaces 2.0 EE GA code:

DOMResponseWriter.writeAttribute

public void writeAttribute(String name, Object value, String property) throws IOException {
      if (null == value) {
          return;
      }
      Attr attribute = document.createAttribute(name.trim());
      attribute.setValue(String.valueOf(value));
      appendToCursor(attribute);
  }

The 3 method arguments output the following:

Name:
Property:null
Value:http://www.w3.org/1999/xhtml

Test case attached.