diff --git a/lib/utils.js b/lib/utils.js
index ce0d7bb7..aadb3e13 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -22,10 +22,7 @@ function arrayString(val) {
     if(i > 0) {
       result = result + ',';
     }
-    if(val[i] instanceof Date) {
-      result = result + JSON.stringify(val[i]);
-    }
-    else if(typeof val[i] === 'undefined') {
+    if(val[i] === null || typeof val[i] === 'undefined') {
       result = result + 'NULL';
     }
     else if(Array.isArray(val[i])) {
@@ -33,8 +30,7 @@ function arrayString(val) {
     }
     else
     {
-      result = result +
-        (val[i] === null ? 'NULL' : JSON.stringify(val[i]));
+      result = result + JSON.stringify(prepareValue(val[i]));
     }
   }
   result = result + '}';
diff --git a/test/unit/utils-tests.js b/test/unit/utils-tests.js
index 45237a97..9cb2a3e4 100644
--- a/test/unit/utils-tests.js
+++ b/test/unit/utils-tests.js
@@ -95,9 +95,24 @@ test('prepareValue: string prepared properly', function() {
   assert.strictEqual(out, 'big bad wolf');
 });
 
-test('prepareValue: array prepared properly', function() {
+test('prepareValue: simple array prepared properly', function() {
   var out = utils.prepareValue([1, null, 3, undefined, [5, 6, "squ,awk"]]);
-  assert.strictEqual(out, '{1,NULL,3,NULL,{5,6,"squ,awk"}}');
+  assert.strictEqual(out, '{"1",NULL,"3",NULL,{"5","6","squ,awk"}}');
+});
+
+test('prepareValue: complex array prepared properly', function() {
+  var out = utils.prepareValue([{ x: 42 }, { y: 84 }]);
+  assert.strictEqual(out, '{"{\\"x\\":42}","{\\"y\\":84}"}');
+});
+
+test('prepareValue: date array prepared properly', function() {
+  helper.setTimezoneOffset(-330);
+
+  var date = new Date(2014, 1, 1, 11, 11, 1, 7);
+  var out = utils.prepareValue([date]);
+  assert.strictEqual(out, '{"2014-02-01T11:11:01.007+05:30"}');
+
+  helper.resetTimezoneOffset();
 });
 
 test('prepareValue: arbitrary objects prepared properly', function() {