I think we need to be more careful about forcing the version to Hibernate 4. Spring 3.1 and 3.2 both still support Hibernate 3 in addition to 4. We'll need to take a similar approach. I believe that will require moving this dependency out of the parent pom altogether, and instead specify both as optional in the spring-flex-core pom, much as is done here: http://repo1.maven.org/maven2/org/springframework/spring-orm/3.2.2.RELEASE/spring-orm-3.2.2.RELEASE.pom