Have a subclass of ufront.db.Object with 4 fields.
Create a new instance and set each field to a value that will not validate (null):
var myObject=new MyObject();
myObject.field1=null;
myObject.field2=null;
myObject.field3=null;
myObject.field4=null;
object.validate();
trace(object.validationErrors);
Result: for each key, the validation error is repeated 4 times, i.e.:
[ field1: [ "field1 is a required field", "field1 is a required field", "field 1 is a required field", "field1 is a required field"] ]
...and so on.