Currently the concerned constraint is not considered when determining the identity of ConstraintViolationImpl (equals() and hashCode()). This causes only one violation to be contained in the set returned by Validator#validate() when validating e.g. the following property:
@Size(min=2, message="must be 2 at least")
@DecimalMin(value="2", message="must be 2 at least")
String name = "1";