better regular expression that actually works

git-svn-id: http://svn.barleysodas.com/barleysodas/trunk@17 0f7b21a7-9e3a-4941-bbeb-ce5c7c368fa7

app/models/page.rb

@@ -16,7 +16,7 @@ class Page < ActiveRecord::Base
   belongs_to :owner, :polymorphic => true
   validates_presence_of :title
   validates_uniqueness_of :title, :scope => 'owner_type'
-  validates_format_of :title, :with => /[A-Za-z0-9 ]/,
+  validates_format_of :title, :with => /^([A-Za-z0-9 ])+$/,
     :message => 'may only contain letters, numbers and spaces'
   before_save :update_html