diff --git a/config/environment.rb b/config/environment.rb
index 811afed..53a9df3 100644
--- a/config/environment.rb
+++ b/config/environment.rb
@@ -75,8 +75,8 @@ Localist.callback = lambda { |l| GetText.locale= l }
 
 Tag.hierarchical = true
 
-# string transliteration
-require 'noosfero/transliterations'
+# several local libraries
+require 'noosfero'
 
 require 'acts_as_filesystem'
 require 'acts_as_searchable'
diff --git a/lib/acts_as_filesystem.rb b/lib/acts_as_filesystem.rb
index 45e577c..a536c77 100644
--- a/lib/acts_as_filesystem.rb
+++ b/lib/acts_as_filesystem.rb
@@ -104,9 +104,7 @@ module ActsAsFileSystem
 
       self[:name] = value
       unless self.name.blank?
-        # FIXME encapsulate this pattern (transliterate -> downcase -> gsub
-        # ...) in a String method, say, to_slug
-        self.slug = self.name.transliterate.downcase.gsub( /[^-a-z0-9~\s\.:;+=_]/, '').gsub(/[\s:;=_+]+/, '-').gsub(/[\-]{2,}/, '-').to_s
+        self.slug = self.name.to_slug
       end
     end
 
diff --git a/lib/noosfero.rb b/lib/noosfero.rb
index 0febdef..5a94a07 100644
--- a/lib/noosfero.rb
+++ b/lib/noosfero.rb
@@ -28,3 +28,4 @@ module Noosfero
 end
 
 require 'noosfero/constants'
+require 'noosfero/core_ext'
diff --git a/lib/noosfero/core_ext.rb b/lib/noosfero/core_ext.rb
new file mode 100644
index 0000000..a09b9d1
--- /dev/null
+++ b/lib/noosfero/core_ext.rb
@@ -0,0 +1 @@
+require 'noosfero/core_ext/string'
diff --git a/lib/noosfero/core_ext/string.rb b/lib/noosfero/core_ext/string.rb
new file mode 100644
index 0000000..eb54a28
--- /dev/null
+++ b/lib/noosfero/core_ext/string.rb
@@ -0,0 +1,7 @@
+require 'noosfero/transliterations'
+
+class String
+  def to_slug
+    transliterate.downcase.gsub( /[^-a-z0-9~\s\.:;+=_]/, '').gsub(/[\s:;=_+]+/, '-').gsub(/[\-]{2,}/, '-').to_s
+  end
+end
--
libgit2 0.21.2