fixed scoping of validation

lib/dao-factory.js

@@ -675,7 +675,14 @@ module.exports = (function() {
 
     return new Utils.CustomEventEmitter(function(emitter) {
       if (options.validate === true) {
-        this.build(attrValueHash).validate().success(function(errors) {
+        var build    = this.build(attrValueHash)
+          , attrKeys = Object.keys(attrValueHash)
+
+        build
+          .validate({
+            skip: Object.keys(build.dataValues).filter(function(val) { return attrKeys.indexOf(val) !== -1 })
+          })
+          .success(function(errors) {
             if (!!errors) {
               emitter.emit('error', errors)
             } else {