macportsのエラー

書くような事でもないですが

sudoCasper:~ onodes$ sudo port install ruby
Password:
Sorry, try again.
Password:
Warning: /opt/local/etc/macports/sources.conf specifies invalid source '<PATH_TO_LOCAL_PORT_TREE>', ignored.
--->  Computing dependencies for ruby
--->  Staging ruby into destroot
Error: Target org.macports.destroot returned: shell command " cd "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_lang_ruby/work/ruby-1.8.7-p249" && /usr/bin/make install install-doc DESTDIR=/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_lang_ruby/work/destroot " returned error 2
Command output: ./miniruby -I./lib -I.ext/common -I./- -r./ext/purelib.rb  ./instruby.rb --make="/usr/bin/make" --dest-dir="/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_lang_ruby/work/destroot" --extout=".ext" --mflags="" --make-flags="DESTDIR=/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_lang_ruby/work/destroot" --data-mode=0644 --prog-mode=0755 --installed-list .installed.list --mantype="doc"
installing binary commands
installing command scripts
installing library scripts
installing headers
installing manpages
installing extension objects
installing extension scripts
Generating RDoc documentation
./miniruby -I./lib -I.ext/common -I./- -r./ext/purelib.rb  ./runruby.rb --extout=.ext  -- "./bin/rdoc" --all --ri --op ".ext/rdoc" "."

Directory .ext/rdoc already exists, but it looks like it
isn't an RDoc directory. Because RDoc doesn't want to risk
destroying any of your existing files, you'll need to
specify a different output directory name (using the
--op <dir> option).

make: *** [rdoc] Error 1

Error: Status 1 encountered during processing.
Before reporting a bug, first run the command again with the -d flag to get complete output.

かいけつ

sudo port clean --work ruby