Ant provides an exec task in order to allow you to fall back on the command line:
<property name="perlmod.dir" location="/tmp/module"/>
<target name="example-mod_build">
<exec dir="${perlmod.dir}" executable="perl" failonerror="true">
<arg line="Makefile.PL"/>
</exec>
<exec dir="${perlmod.dir}" executable="make" failonerror="true"/>
<exec dir="${perlmod.dir}" executable="make" failonerror="true">
<arg line="test"/>
</exec>
<exec dir="${perlmod.dir}" executable="make" failonerror="true">
<arg line="install"/>
</exec>
</target>
(See: Exec)
I should point out that this isn't something I've ever needed to do, but if I had to, this is how I'd go about it.
Hope this helps.