Do boost::shared_ptr<T> and boost::shared_ptr<const T> share the reference count?

There are several interesting questions on pitfalls with boost::shared_ptrs. In one of them, there is the useful tip to avoid pointing boost::shared_ptr<Base> and boost::shared_ptr<Derived> to the same object of type Derived since they use different reference counts and might destroy the object prematurely.

My question: Is it safe to have both boost::shared_ptr<T> and boost::shared_ptr<const T> point to the same object of type T, or will this cause the same problem?