diff --git a/ChangeLog b/ChangeLog
index 3b92ae78ee..112c3f5c19 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Tue Dec 23 15:36:58 2008  Yuki Sonoda (Yugui)  <yugui@yugui.jp>
+
+	* tool/file2lastrev.rb: detects vcs directory properly on building
+	  outside of srcdir. [ruby-dev:37555] [ruby-dev:37561]
+
 Tue Dec 23 15:30:02 2008  NAKAMURA Usaku  <usa@ruby-lang.org>
 
 	* io.c (pipe_open): need to initialize args.
diff --git a/tool/file2lastrev.rb b/tool/file2lastrev.rb
index f8f1470574..430aca6730 100644
--- a/tool/file2lastrev.rb
+++ b/tool/file2lastrev.rb
@@ -3,17 +3,13 @@
 require 'optparse'
 require 'pathname'
 
+SRCDIR = Pathname(File.dirname($0)).parent.freeze
 class VCSNotFoundError < RuntimeError; end
 
 def detect_vcs(path)
-  target_path = Pathname(File.expand_path(path))
-
-  path = target_path.directory? ? target_path : target_path.parent  
-  begin
-    return :svn, target_path.relative_path_from(path) if File.directory?("#{path}/.svn")
-    return :git, target_path.relative_path_from(path) if File.directory?("#{path}/.git")
-    path, orig = path.parent, path
-  end until path == orig
+  path = SRCDIR
+  return :svn, path.relative_path_from(SRCDIR) if File.directory?("#{path}/.svn")
+  return :git, path.relative_path_from(SRCDIR) if File.directory?("#{path}/.git")
   raise VCSNotFoundError, "does not seem to be under a vcs"
 end
 
@@ -23,9 +19,9 @@ def get_revisions(path)
 
   info = case vcs
   when :svn
-    `svn info #{path}`
+    `cd '#{SRCDIR}' && svn info '#{path}'`
   when :git
-    `git svn info #{path}`
+    `cd '#{SRCDIR}' && git svn info '#{path}'`
   end
 
   if info =~ /^Revision: (\d+)$/