c#silverlight logging silverlight-5.0 unhandled-exception

how to log Unhandled Exception in Silverlight 5

I would like to capture and log unhandled exceptions that occur in my Silverlight 5 application. I already have wired up the Application.UnhandledException delegate. The question is, after an exception has been thrown, what can and what can't I do? This Silverlight application is running in a C++ application that is hosting the WebControl (IE's engine) and this host is implementing the external function. So this is what the Application.UnhandledException's function looks like:

private void Application_UnhandledException(object sender, ApplicationUnhandledExceptionEventArgs e)
{
    var ex = e.ExceptionObject;

    // This is a reference to the 
    var external = External.Instance;

    // loop through all the exceptions and call the hosts 'external' method so the
    // host is able to write out the error to a local log file
    while (external != null && ex != null)
    {
        external.LogException(ex.Message, ex.StackTrace);
        ex = ex.InnerException;
    }

    // If the app is running outside of the debugger then report the exception using
    // a ChildWindow control.
    if (!System.Diagnostics.Debugger.IsAttached)
    {
        // NOTE: This will allow the application to continue running after an exception has been thrown
        // but not handled. 
        // For production applications this error handling should be replaced with something that will 
        // report the error to the website and stop the application.
        e.Handled = true;
        ChildWindow errorWin = new ErrorWindow(e.ExceptionObject);
        errorWin.Show();
    }
}

The goal is to log the error and keep the application running.

Solution

A standard System.Diagnostics target to enable capturing using DebugView, etc.
An asynchronous Web service target similar to the one in NLog.
An isolated storage target with deferred transfer to server semantics