I need to specify a list of simple properties in plugin configuration.  When I define this in plugin descriptor:

            <plugin-configuration>
                <c:list-property name="acceptablePingStatusCodes" displayName="Accepable Ping Status Codes" required="false">
                   <c:description>If specified, these are the only HTTP status codes that makes the URL considered 'available'.  If not set, just successfully connecting to the URL makes the application considered available.</c:description>
                   <c:simple-property name="statusCode" type="integer" />
                </c:list-property>
            </plugin-configuration>

I get this in the UI when it tries to render it:

Rendering of lists of PropertyDefinitionSimple properties is not yet supported. Here's the list's toString() value for now: [PropertySimple[id=501607, name=statusCode, value=200, override=false]]