How to detect negative number in Zend Framework Router Regex

I have the following .ini configuration that works fine for positive integers but not negative integers.

routes.nd.type = "Zend_Controller_Router_Route_Regex"
routes.nd.route = "news/(\d+)/d"
routes.nd.defaults.controller = "news"
routes.nd.defaults.action = "display"
routes.nd.map.id = 1

      

        
        
        
      

    

How to get negative integers to be detected? Apparently \d+

ignores negative numbers.

Can't find this in the ZF docs.

considers