Buenos días,
al final hice algo así y me funciona correctamente:
Código XML:
Ver original<project name="all" basedir="." default="buildall">
<target name="buildfrontend">
<ant dir="../frontend" target="export"/>
</target>
<target name="buildcore" depends="buildfrontend">
<ant dir="../core" target="export"/>
</target>
<target name="buildfrontendposterior" depends="buildfrontend,buildcore">
<ant dir="../frontend" target="export"/>
</target>
<target name="buildweb" depends="buildcore,buildfrontend,buildfrontendposterior">
<ant dir="../web" target="deploy"/>
</target>
<target name="buildall" depends="buildweb"/>
</project>
Un saludo!!