When accessing a cgi web service ,it throws the error [there is an error in xml document(]
this error happens only If the return paramater is an array of objects

how to resolve this?

------------execption details---------------
 System.InvalidOperationException was unhandled
 Message="There is an error in XML document (1, 452)."
 Source="System.Xml"
 StackTrace:
 at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader, String encodingStyle, XmlDeserializationEvents events)
 at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader, String encodingStyle)
 at System.Web.Services.Protocols.SoapHttpClientProtocol.ReadResponse(SoapClientMessage message, WebResponse response, Stream responseStream, Boolean asyncCall)
 at System.Web.Services.Protocols.SoapHttpClientProtocol.Invoke(String methodName, Object[] parameters)
 at MyWebService.CallMyMethod(String hostName, String YourAppMyApptoken, Int32 subscription\_id) in D:\Samjog\Temp Project\ProxyTest\ProxyTest\MyWebService.cs:line 93
 at ProxyTest.Form1.btnListFeeds\_Click(Object sender, EventArgs e) in D:\Samjog\Temp Project\ProxyTest\ProxyTest\Form1.cs:line 209
 at System.Windows.Forms.Control.OnClick(EventArgs e)
 at System.Windows.Forms.Button.OnClick(EventArgs e)
 at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
 at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
 at System.Windows.Forms.Control.WndProc(Message& m)
 at System.Windows.Forms.ButtonBase.WndProc(Message& m)
 at System.Windows.Forms.Button.WndProc(Message& m)
 at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
 at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
 at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
 at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
 at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(Int32 dwComponentID, Int32 reason, Int32 pvLoopData)
 at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
 at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
 at System.Windows.Forms.Application.Run(Form mainForm)
 at ProxyTest.Program.Main() in D:\Samjog\Temp Project\ProxyTest\ProxyTest\Program.cs:line 18
 at System.AppDomain.\_nExecuteAssembly(Assembly assembly, String[] args)
 at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
 at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
 at System.Threading.ThreadHelper.ThreadStart\_Context(Object state)
 at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
 at System.Threading.ThreadHelper.ThreadStart()
 InnerException: System.InvalidCastException
 Message="Cannot assign object of type System.Int32 to an object of type MyAppWSDLSubscribedFeedInfo."
 Source="dz-gayew"
 StackTrace:
 at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationReaderMyWebService.Read19\_CallMyMethodResponse()
 at Microsoft.Xml.Serialization.GeneratedAssembly.ArrayOfObjectSerializer14.Deserialize(XmlSerializationReader reader)
 at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader, String encodingStyle, XmlDeserializationEvents events)
 InnerException: