diff --git a/plugins/stoa/lib/stoa_plugin.rb b/plugins/stoa/lib/stoa_plugin.rb
index 01b60bb..ed9c5e4 100644
--- a/plugins/stoa/lib/stoa_plugin.rb
+++ b/plugins/stoa/lib/stoa_plugin.rb
@@ -60,12 +60,14 @@ class StoaPlugin < Noosfero::Plugin
   end
 
   def account_controller_filters
+    environment = context.environment
     block = lambda do
       params[:profile_data] ||= {}
       params[:profile_data][:invitation_code] = params[:invitation_code]
+      invitation = Task.pending.find(:first, :conditions => {:code => params[:invitation_code]})
       if request.post?
-        if !params[:invitation_code] && !StoaPlugin::UspUser.matches?(params[:profile_data][:usp_id], params[:confirmation_field], params[params[:confirmation_field]])
-          @person = Person.new
+        if !invitation && !StoaPlugin::UspUser.matches?(params[:profile_data][:usp_id], params[:confirmation_field], params[params[:confirmation_field]])
+          @person = Person.new(:environment => environment)
           @person.errors.add(:usp_id, _(' validation failed'))
           render :action => :signup
         end
diff --git a/plugins/stoa/lib/stoa_plugin/usp_user.rb b/plugins/stoa/lib/stoa_plugin/usp_user.rb
index 0fc9087..71d30b1 100644
--- a/plugins/stoa/lib/stoa_plugin/usp_user.rb
+++ b/plugins/stoa/lib/stoa_plugin/usp_user.rb
@@ -13,6 +13,8 @@ class StoaPlugin::UspUser < ActiveRecord::Base
   end
 
   def self.matches?(usp_id, field, value)
+    usp_id.gsub!(/[.-]/,'')
+    value.gsub!(/[.-]/,'')
     user = StoaPlugin::UspUser.find_by_codpes(usp_id.to_i)
     return false if user.nil? || !user.respond_to?(field) || value.blank?
     case field.to_sym
--
libgit2 0.21.2