build.xml

<project default="all">
    <target name="clean">
        <exec executable="mvn" failonerror="true">
            <arg line="-f pom-new-plugin.xml clean" />
        </exec>
        <exec executable="mvn" failonerror="true">
            <arg line="-f pom-old-plugin.xml clean" />
        </exec>
    </target>
    <target name="install">
        <exec executable="mvn" failonerror="true">
            <arg line="-f pom-new-plugin.xml install" />
        </exec>
        <exec executable="mvn" failonerror="true">
            <arg line="-f pom-old-plugin.xml install" />
        </exec>
    </target>
    <target name="all">
        <exec executable="mvn" failonerror="true">
            <arg line="-f pom-new-plugin.xml clean install" />
        </exec>
        <exec executable="mvn" failonerror="true">
            <arg line="-f pom-old-plugin.xml clean install" />
        </exec>
    </target>
</project>