StackoverflowException while using SqlDependencies with Ef Framework - entity-framework

Question

I would like to get some feedback about using SqlDependencies with EF Framework 4.0. I have currently implemented a scenario using ObjectQuery in combination with toStraceString() to generate SqlDependency.
Im getting a StackoverflowException somewhere in Entity Framework source code when doing refresh store wins. I thought this error would somewhere in my code, but i cannot find it.
I made up a small example of what i want to do:
public partial class MainWindow : Window
{
private SqlDependency _sqldep;
public delegate void DataChanged(string test);
TestEntities m = new TestEntities();
SqlCommand _cmd;
public MainWindow()
{
InitializeComponent();
this.DataContext = this;
//m.Connection.Open();
SqlDependency.Start(((System.Data.EntityClient.EntityConnection)m.Connection).StoreConnection.ConnectionString);
var query = m.User.AsQueryable<User>();
string query_str = m.User.ToTraceString();
SqlConnection con = new SqlConnection(((System.Data.EntityClient.EntityConnection)m.Connection).StoreConnection.ConnectionString);
con.Open();
SqlCommand cmd = new SqlCommand(query_str, con);
_cmd = cmd;
_sqldep = new SqlDependency(cmd);
_sqldep.OnChange += dependency_OnChange;
cmd.ExecuteReader();
this.Users = m.User;
}
SqlDependency dependency;
// Bei Änderung am gegebenen SQL-Statement
private void dependency_OnChange(object sender, SqlNotificationEventArgs e)
{
dependency = (SqlDependency)sender;
dependency.OnChange -= dependency_OnChange;
NotifierOnDataChanged(string.Empty);
dependency.OnChange += dependency_OnChange;
}
private void NotifierOnDataChanged(string bla)
{
try
{
m.Refresh(System.Data.Objects.RefreshMode.StoreWins, m.User);
}
catch (System.Exception ex)
{
System.Windows.MessageBox.Show(ex.Message, "Fehler");
}
}
private IEnumerable<User> _users;
public IEnumerable<User> Users
{
get { return _users; }
set { _users = value; }
}
}
I'm getting my StackoverflowException at NotifierOnDataChanged -> Refresh