diff --git a/Library/Homebrew/cmd/doctor.rb b/Library/Homebrew/cmd/doctor.rb
index 35631956c4..1bab04a7d7 100644
--- a/Library/Homebrew/cmd/doctor.rb
+++ b/Library/Homebrew/cmd/doctor.rb
@@ -204,7 +204,7 @@ def check_for_broken_symlinks
   Keg::PRUNEABLE_DIRECTORIES.each do |d|
     next unless d.directory?
     d.find do |pn|
-      broken_symlinks << pn if pn.symlink? and pn.readlink.expand_path.to_s =~ /^#{HOMEBREW_PREFIX}/ and not pn.exist?
+      broken_symlinks << pn if pn.symlink? and pn.readlink.expand_path.to_s =~ /^#{HOMEBREW_PREFIX}/o and not pn.exist?
     end
   end
   unless broken_symlinks.empty? then <<-EOS.undent