SpringValidationMatchers is a project mainly written in ..., it's free.
Custom Hamcrest Matchers to test Spring MVC validators errors on fields and codes in a fluid fashion
This extends hamcrest matchers to provide useful matchers for spring mvc validator
http://code.google.com/p/hamcrest/wiki/MatcherLibraries
TODO create maven repo in github to host it
http://cemerick.com/2010/08/24/hosting-maven-repos-on-github/