--- JsonMapper.cs       24 Apr 2008 23:16:16 -0000      1.1
+++ JsonMapper.cs       24 Apr 2008 23:16:54 -0000
@@ -739,7 +739,11 @@
             if (obj is IDictionary) {
                 writer.WriteObjectStart ();
                 foreach (DictionaryEntry entry in (IDictionary) obj) {
-                    writer.WritePropertyName ((string) entry.Key);
+                       if (entry.Key is DateTime)
+                           writer.WritePropertyName ( entry.Key.ToString() );
+                    else
+                           writer.WritePropertyName ((string) entry.Key);
+
                     WriteValue (entry.Value, writer, writer_is_private,
                                 depth + 1);
                 }