Object validation error not binding to error in taglib.

Using the form taglib "http://www.springframework.org/tags/form" I can display
object validation errors in Spring MVC with

<form:errors/>

i.e. with no path element.

When used with Webflow, this no longer works.

Using this tag causes getGlobalErrors() to be called.

Spring webflow's implementation of this method in BindingModel looks for a Message with a status of null.
However object validation errors created with Hibernate Validator hava a status of "" and are not matched.