This fixes the installation of binaries if PKGMK_WORK_DIR is something like
   /home/foo/.tmp/pkgmk/work/$name
 
diff -aur ruby-1.9.2-p0.orig/tool/rbinstall.rb ruby-1.9.2-p0/tool/rbinstall.rb
--- ruby-1.9.2-p0.orig/tool/rbinstall.rb	2010-07-24 12:37:26.000000000 +0200
+++ ruby-1.9.2-p0/tool/rbinstall.rb	2010-09-02 10:41:21.417001125 +0200
@@ -404,7 +404,6 @@
   end
   for src in Dir[File.join(srcdir, "bin/*")]
     next unless File.file?(src)
-    next if /\/[.#]|(\.(old|bak|orig|rej|diff|patch|core)|~|\/core)$/i =~ src
 
     name = RbConfig.expand(trans[File.basename(src)])