Merge pull request #332 from catlion/master

JsonSerializer.SerializeToString throws OutOfRangeException

Author: mythz

src/ServiceStack.Text/DateTimeExtensions.cs

@@ -46,7 +46,7 @@ public static long ToUnixTimeMs(this DateTime dateTime)
             var dtUtc = dateTime;
             if (dateTime.Kind != DateTimeKind.Utc)
             {
-                dtUtc = dateTime.Kind == DateTimeKind.Unspecified
+                dtUtc = dateTime.Kind == DateTimeKind.Unspecified && dateTime > DateTime.MinValue
                     ? DateTime.SpecifyKind(dateTime.Subtract(LocalTimeZone.GetUtcOffset(dateTime)), DateTimeKind.Utc)
                     : dateTime.ToStableUniversalTime();
             }
@@ -184,4 +184,4 @@ public static DateTime EndOfLastMonth(this DateTime from)
         }
     }
 
-}
+}