Unable to generate class model after modifying my *-items.xml file

Here's my *-items.xml file :

    <?xml version="1.0" encoding="ISO-8859-1"?>
<items   xmlns:xsi="http://ift.tt/ra1lAU"
            xsi:noNamespaceSchemaLocation="items.xsd">
    <enumtypes>
        <enumtype code="StadiumType" autocreate="true" generate="true" dynamic="false">
            <value code="openair"/>
            <value code="enclosed"/>
        </enumtype>
        <enumtype code="StadiumAccess" autocreate="true" generate="true" dynamic="true">
            <value code="road"/>
            <value code="rail"/>
            <value code="plane"/>
        </enumtype>
    </enumtypes>
    <relations>
        <relation code="StadiumMatchRelation"
                localized="false" generate="true" autocreate="true">
            <sourceElement type="Stadium" qualifier="stadium" cardinality="one"/>
            <targetElement type="Match" qualifier="matches" cardinality="many"/>
        </relation>
    </relations>

    <itemtypes>
        <itemtype code="Stadium" generate="true" autocreate="true">
            <deployment table="CuppyTrailStadium" typecode="10123" />
            <attributes>
                <attribute qualifier="code" type="java.lang.String" >
                    <persistence type="property"/>
                    <modifiers optional="false" unique="true"/>
                </attribute>
                <attribute qualifier="capacity" type="java.lang.Integer">
                    <description>Capacity</description>
                    <persistence type="property" />
                </attribute>
                <attribute type="StadiumType" qualifier="StadiumType">
                <persistence type="property"/>
                <defaultvalue>em().getEnumerationValue("StadiumType","openair")</defaultvalue>
                </attribute>
            </attributes>
        </itemtype>
    </itemtypes>
</items>

After building with "ant clean all" in cmd , and refreshing my project list. I am unable to find autogenerated model classes under platform/bootstrap...

any advice ?

ps : am working on wiki.hybris.com tutorials