def METHOD_NAME(proot, source, env, kw):
    # make sure the packageroot is a Dir object.
    if SCons.Util.is_String(proot): proot=env.Dir(proot)
    #  create the specfile builder
    s_bld=SCons.Builder.Builder(
        action  = build_specfiles,
        )
    # create the specfile targets
    spec_target=[]
    control=proot.Dir('CONTROL')
    spec_target.append(control.File('control'))
    spec_target.append(control.File('conffiles'))
    spec_target.append(control.File('postrm'))
    spec_target.append(control.File('prerm'))
    spec_target.append(control.File('postinst'))
    spec_target.append(control.File('preinst'))
    # apply the builder to the specfile targets
    s_bld(env, spec_target, source, **kw)
    # the packageroot directory does now contain the specfiles.
    return proot