EKCalendar标题崩溃应用程序（MonoTouch.EventKit.EKCalendar.set_Title）

Question

我在MonoTouch.EventKit中遇到EKCalendar问题。当我尝试通过属性设置标题时，应用程序崩溃。它不会每次都发生，只发生两次。以下是我的日志片段：

Apr 29 16:49:19 iPad[973] <Error>: Stacktrace:
Apr 29 16:49:19 iPad[973] <Error>:   at <unknown> <0xffffffff>
Apr 29 16:49:19 iPad[973] <Error>:   at (wrapper managed-to-native) MonoTouch.ObjCRuntime.Messaging.void_objc_msgSend_IntPtr (intptr,intptr,intptr) <0xffffffff>    
Apr 29 16:49:19 iPad[973] <Error>:   at MonoTouch.EventKit.EKCalendar.set_Title (string) [0x0001b] in /Developer/MonoTouch/Source/monotouch/src/EventKit/.pp-EKCalendar.g.cs:134
Apr 29 16:49:19 iPad[973] <Error>:   at OverwriteEKCalendar (MonoTouch.EventKit.EKCalendar) [0x00022] in \Services\Calendar\EKCalendarTouch.cs:229
Apr 29 16:49:19 iPad[973] <Error>:   at Services.Calendar.CalendarService.OverwriteCalendar

代码非常简单：

public void OverwriteEKCalendar(EKCalendar calendar)
{
    if (this.CGColor != null)
    {
        calendar.CGColor = this.CGColor.ToCGColor();
    }

    calendar.Title = this.Title;
}

你知道发生了什么吗？