How do I use my own compiler with Nant?

<target name="build.application">
    <exec program="dcc32" basedir="${Delphi.Bin}" workingdir="${Application.Folder}" verbose="true">
        <arg value="${Application.Compiler.Directive}" />
        <arg value="-Q" />
        <arg value="/B" />
        <arg value="/E${Application.Output.Folder}" />
        <arg value="/U${Application.Lib.Folder};${Application.Search.Folder}" />
        <arg value="${Application.Folder}${Delphi.Project}" />
    </exec>
</target>