fixed regular expression in Specifying Constraints section

railties/guides/source/routing.textile

@@ -650,15 +650,15 @@ h4. Specifying Constraints
 You can use the +:constraints+ option to specify a required format on the implicit +id+. For example:
 
 <ruby>
-resources :photos, :constraints => {:id => /[A-Z][A-Z][0-9]+/}
+resources :photos, :constraints => {:id => /[a-z][A-Z][0-9]+/}
 </ruby>
 
 This declaration constrains the +:id+ parameter to match the supplied regular expression. So, in this case, the router would no longer match +/photos/1+ to this route. Instead, +/photos/RR27+ would match.
 
 You can specify a single constraint to apply to a number of routes by using the block form:
 
 <ruby>
-constraints(:id => /[A-Z][A-Z][0-9]+/) do
+constraints(:id => /[a-z][A-Z][0-9]+/) do
   resources :photos
   resources :accounts
 end