cd /usr/ports/www/opera && make deinstall
===> Deinstalling for www/opera
===> Deinstalling opera-9.20.20070409
pkg_delete: package 'opera-9.20.20070409' is required by these other packages
and may not be deinstalled (but I'll delete it anyway):
opera-linuxplugins-9.10.20061214
pkg_delete: unable to completely remove directory '/usr/local/share/opera/bin'
pkg_delete: unable to completely remove directory '/usr/local/share/opera'
pkg_delete: couldn't entirely delete package (perhaps the packing list is
incorrectly specified?)