Commented Unassigned: C# App crashes while getting row from dataframe [150]

Hi,
Can anyone help me on this.
I am facing this weird issue, when I try to fetch some rows(row by row) from my dataset(dataframe in R). First few rows are fetched without any error but after say 4-5 rows I get some exception on a line which executed perfectly for first few rows.
I am executing following statement:

SomeRDotNetObject.Evaluate("Dataset1[rowindex , ]" ); // Dataset1 is the name of the dataset

for say rowindex= 1 to 4 this works but fails on rowindex=5. And C# application crashes with following exception:-

_System.Windows.Threading.DispatcherUnhandledExceptionEventHandler -METHOD :Invoke() -LINE :0
System.InvalidOperationException: Dispatcher processing has been suspended, but messages are still being processed.
at System.Windows.Threading.Dispatcher.WndProcHook(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o)
at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
at MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(Object source, Delegate method, Object args, Int32 numArgs, Delegate catchHandler)_


Thanks
adabral
Comments: The scrolling issue is a WPF issue and its a fairly standard cross-thread problem, the reason it is difficult to figure out is because R itself is trying to do something with the the Windows message queue