diff --git a/lib/Drivers/DML/mongodb.js b/lib/Drivers/DML/mongodb.js
index 45fc3657..789d4bd5 100644
--- a/lib/Drivers/DML/mongodb.js
+++ b/lib/Drivers/DML/mongodb.js
@@ -105,7 +105,7 @@ Driver.prototype.close = function (cb) {
 Driver.prototype.find = function (fields, table, conditions, opts, cb) {
 	var collection = this.db.collection(table);
 
-	convertToDB(conditions, this.config.timezone);
+	convertToDB(conditions, this.config.timezone, this.config.enableGeneralID);
 
 	var cursor = (fields ? collection.find(conditions, fields) : collection.find(conditions));
 
@@ -159,7 +159,7 @@ Driver.prototype.find = function (fields, table, conditions, opts, cb) {
 Driver.prototype.count = function (table, conditions, opts, cb) {
 	var collection = this.db.collection(table);
 
-	convertToDB(conditions, this.config.timezone);
+	convertToDB(conditions, this.config.timezone, this.config.enableGeneralID);
 
 	var cursor     = collection.find(conditions);
 
@@ -186,7 +186,7 @@ Driver.prototype.count = function (table, conditions, opts, cb) {
 };
 
 Driver.prototype.insert = function (table, data, id_prop, cb) {
-	convertToDB(data, this.config.timezone);
+	convertToDBTypes(data, this.config.timezone, this.config.enableGeneralID);
 
 	return this.db.collection(table).insert(
 		data,
@@ -325,8 +325,8 @@ Driver.prototype.hasMany = function (Model, association) {
 };
 
 Driver.prototype.update = function (table, changes, conditions, cb) {
-	convertToDB(changes, this.config.timezone);
-	convertToDB(conditions, this.config.timezone);
+	convertToDBTypes(changes, this.config.timezone, this.config.enableGeneralID);
+	convertToDB(conditions, this.config.timezone, this.config.enableGeneralID);
 
 	return this.db.collection(table).update(
 		conditions,
@@ -342,7 +342,7 @@ Driver.prototype.update = function (table, changes, conditions, cb) {
 };
 
 Driver.prototype.remove = function (table, conditions, cb) {
-	convertToDB(conditions, this.config.timezone);
+	convertToDB(conditions, this.config.timezone, this.config.enableGeneralID);
 
 	return this.db.collection(table).remove(conditions, cb);
 };
@@ -351,7 +351,7 @@ Driver.prototype.clear = function (table, cb) {
 	return this.db.collection(table).remove(cb);
 };
 
-function convertToDB(obj, timeZone) {
+function convertToDB(obj, timeZone, enableGeneralID) {
 	for (var k in obj) {
 		if ([ 'and', 'or', 'not' ].indexOf(k) >= 0) {
 			for (var j = 0; j < obj[k].length; j++) {
@@ -363,14 +363,20 @@ function convertToDB(obj, timeZone) {
 		}
 		if (Array.isArray(obj[k]) && k[0] != '$') {
 			for (var i = 0; i < obj[k].length; i++) {
-				obj[k][i] = convertToDBVal(k, obj[k][i], timeZone);
+				obj[k][i] = convertToDBVal(k, obj[k][i], timeZone, enableGeneralID);
 			}
 
 			obj[k] = { $in: obj[k] };
 			continue;
 		}
 
-		obj[k] = convertToDBVal(k, obj[k], timeZone);
+		obj[k] = convertToDBVal(k, obj[k], timeZone, enableGeneralID);
+	}
+}
+
+function convertToDBTypes(obj, timeZone, enableGeneralID) {
+	for (var k in obj) {
+		obj[k] = convertToDBType(k, obj[k], timeZone, enableGeneralID);
 	}
 }
 
@@ -387,9 +393,22 @@ function convertFromDB(obj, timezone) {
 	}
 }
 
-function convertToDBVal(key, value, timezone) {
+function convertToID(value, enableGeneralID) {
+	if (enableGeneralID && value != null && 'number' != typeof value && (value.length != 12 && value.length != 24)) {
+		return value;
+	} else {
+		return mongodb.ObjectID(value);
+	}
+}
+
+function convertToDBVal(key, value, timezone, enableGeneralID) {
 	if (value && typeof value.sql_comparator == "function") {
-		var val       = (key != "_id" ? value : new mongodb.ObjectID(value));
+		var val;
+		if (key == "_id") {
+			val = convertToID(value.val, enableGeneralID);
+		} else {
+			val = value.val;
+		}
 		var comp      = value.sql_comparator();
 		var condition = {};
 
@@ -416,12 +435,18 @@ function convertToDBVal(key, value, timezone) {
 		return condition;
 	}
 
+	return convertToDBType(key, value, timezone, enableGeneralID);
+
+}
+
+function convertToDBType(key, value, timezone, enableGeneralID) {
+
 	if (Buffer.isBuffer(value)) {
 		return new mongodb.Binary(value);
 	}
 
 	if (key == "_id" && typeof value == "string") {
-		value = new mongodb.ObjectID(value);
+		value = convertToID(value, enableGeneralID);
 	}
 
 	return value;
diff --git a/lib/Instance.js b/lib/Instance.js
index 859be697..51b9daa6 100755
--- a/lib/Instance.js
+++ b/lib/Instance.js
@@ -108,6 +108,12 @@ function Instance(Model, opts) {
 		}
 		instance_saving = true;
 
+		for (var k in Model.properties) {
+			if (opts.changes.indexOf(k) == -1 &&
+					(Model.properties[k].type == 'array' || Model.properties[k].type == 'object'))
+				opts.changes.push(k);
+		}
+
 		handleValidations(function (err) {
 			if (err) {
 				return saveError(cb, err);
@@ -510,7 +516,7 @@ function Instance(Model, opts) {
 		Object.defineProperty(instance, k, {
 			value      : opts.methods[k].bind(instance),
 			enumerable : false,
-			writable  : true
+			writeable  : true
 		});
 	}
 
diff --git a/lib/Property.js b/lib/Property.js
index fdfc6ba4..0107e04b 100644
--- a/lib/Property.js
+++ b/lib/Property.js
@@ -2,7 +2,7 @@ var _        = require('lodash');
 var ORMError = require("./Error");
 
 var KNOWN_TYPES = [
-	"text",   "number", "integer", "boolean", "date", "enum", "object",
+	"text",   "number", "integer", "boolean", "date", "enum", "object", "array",
 	"binary", "point",  "serial"
 ];
 
@@ -24,6 +24,9 @@ exports.normalize = function (opts) {
 			case "Object":
 				opts.prop = { type: "object" };
 				break;
+			case "Array":
+				opts.prop = { type: "array" };
+				break;
 			case "Buffer":
 				opts.prop = { type: "binary" };
 				break;
@@ -40,7 +43,7 @@ exports.normalize = function (opts) {
 
 	if (KNOWN_TYPES.indexOf(opts.prop.type) === -1 && !(opts.prop.type in opts.customTypes)) {
 		throw new ORMError("Unknown property type: " + opts.prop.type, 'NO_SUPPORT');
-  }
+	}
 
 	if (!opts.prop.hasOwnProperty("required") && opts.settings.get("properties.required")) {
 		opts.prop.required = true;