Convention cannot work when "struts.convention.result.flatLayout" set to FALSE

<struts>
    <constant name="struts.convention.action.suffix" value="Controller"/>
    <constant name="struts.convention.action.mapAllMatches" value="true"/>
    <constant name="struts.convention.default.parent.package" value="rest-default"/>

    <constant name="struts.convention.package.locators" value="example"/>
    <constant name="struts.i18n.reload" value="true"/>
	<constant name="struts.devMode" value="true"/>
	<constant name="struts.convention.result.flatLayout" value="false"/> 
	<constant name="struts.convention.classes.reload" value="true" />    
	<constant name="struts.convention.action.includeJars" value="false" />
    <constant name="struts.convention.exclude.packages" value="org.apache.struts.*,org.apache.struts2.*,org.springframework.web.struts.*,org.springframework.web.struts2.*,org.hibernate.*"/>
</struts>

<pre>
/*
 * $Id: DefaultResultMapBuilder.java 1099705 2011-05-05 07:17:33Z jogep $
 */

//...

  public class DefaultResultMapBuilder implements ResultMapBuilder {

//...

    protected void makeResults(Class<?> actionClass, String path, String resultPrefix,
            Map<String, ResultConfig> results, PackageConfig packageConfig,
            Map<String, ResultTypeConfig> resultsByExtension) {
        if (path.startsWith(resultPrefix)) {
            int indexOfDot = path.indexOf('.', resultPrefix.length());

            // This case is when the path doesn't contain a result code
            
/*L363*/    if (indexOfDot == resultPrefix.length() || !flatResultLayout) {
                if (LOG.isTraceEnabled()) {
                    LOG.trace("The result file [#0] has no result code and therefore" +
                        " will be associated with success, input and error by default. This might" +
                        " be overridden by another result file or an annotation.", path);
                }

</pre>