Bug 176450 Support link to CSS Feature(Model Part)
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/command/PropertyCommand.java
if ( !isGroupNameValidInContext( (String) value ) )
				throw new NameException( element, (String) value,
						NameException.DESIGN_EXCEPTION_DUPLICATE );
		}
		
		if ( prop.isIntrinsic( ) )
		{
			setIntrinsicProperty( prop, value );
		}
		else
		{
			if ( IDesignElementModel.REF_TEMPLATE_PARAMETER_PROP.equals( prop
					.getName( ) )
					&& value == null )
				clearRefTemplateParameterProp( prop, value );
			else
				doSetProperty( prop, value );
		}
	}
	/**
	 * Remove template definition from module if the definition is no longer
	 * refferenced when setting
	 * <code>IDesignElementModel.REF_TEMPLATE_PARAMETER_PROP</code> null.
	 * 
	 * @param prop
	 *            should be
	 *            <code>IDesignElementModel.REF_TEMPLATE_PARAMETER_PROP</code>.
	 * @param value
	 *            should be null;
	 * @throws SemanticException