Should accept path prefixes not starting with slash.

CHANGELOG.rdoc

@@ -6,6 +6,9 @@
   * Warden 0.9.0 compatibility
   * Mongomapper 0.6.10 compatibility
 
+* bug fix
+  * Accept path prefix not starting with slash
+
 == 0.8.2
 
 * enhancements

lib/devise/mapping.rb

@@ -61,9 +61,8 @@ def initialize(name, options) #:nodoc:
       @as    = (options.delete(:as) || name).to_sym
       @klass = (options.delete(:class_name) || name.to_s.classify).to_s
       @name  = (options.delete(:scope) || name.to_s.singularize).to_sym
-      @path_names  = options.delete(:path_names) || {}
-      @path_prefix = options.delete(:path_prefix).to_s
-      @path_prefix << "/" unless @path_prefix[-1] == ?/
+      @path_names = options.delete(:path_names) || {}
+      @path_prefix = "/#{options.delete(:path_prefix)}/".squeeze("/")
       @route_options = options || {}
 
       setup_path_names

test/rails_app/config/routes.rb

@@ -1,7 +1,7 @@
 ActionController::Routing::Routes.draw do |map|
   map.devise_for :users
   map.devise_for :admin, :as => 'admin_area'
-  map.devise_for :accounts, :scope => 'manager', :path_prefix => '/:locale',
+  map.devise_for :accounts, :scope => 'manager', :path_prefix => ':locale',
     :class_name => "User", :requirements => { :extra => 'value' }, :path_names => {
       :sign_in => 'login', :sign_out => 'logout', :password => 'secret',
       :confirmation => 'verification', :unlock => 'unblock'