remove old installations

[Roger Pack]

Hello all.
I was attempting to add this line to a Port:

fetch {
    system "rm -rf ${worksrcpath}"

however it doesn't seem to work as I would have expected it to (to
clean up that directory).

Error: Target org.macports.fetch returned: bad option rm -rf
/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_multimedia_mplayer-devel/mplayer-devel/work/trunk


Any pointers for me on it?
Thanks.
-r