GtkLabel and win32

[<misterdebrrr sympatico ca>]

Below is a some code that produces a GTK Window, adds a GTK Label to it 
and shows both. The problem I'm having is that IF I move a window on part of the Label, often, the text won't 
get redrawn when I move the window off it. This means I often get a Label that shows 'B' and nothing else. 
For some odd reason, the B always gets drawn no matter what. Can anyone help me ?

(code is below)

#include <gtk/gtk.h>

static void before_main_destroy(GtkWidget *widget, gpointer data);

int main(int argc, char *argv[])
{
GtkWidget *window;
GtkWidget *label;

gtk_init (&argc, &argv);

window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
gtk_window_set_title (GTK_WINDOW (window), "This is a window !");
gtk_window_set_resizable (GTK_WINDOW (window), FALSE);
g_signal_connect (G_OBJECT (window), "destroy", G_CALLBACK 
(before_main_destroy), NULL);

label = gtk_label_new ("Brrr");
gtk_container_add (GTK_CONTAINER (window), label);
gtk_widget_show (label);

gtk_widget_show(window);
gdk_window_set_decorations (GDK_WINDOW(window->window), GDK_DECOR_TITLE 
| GDK_DECOR_MENU);
 
gtk_main ();

return 0;
}

static void before_main_destroy(GtkWidget *widget, gpointer data)
{
gtk_main_quit ();
}

#include <gtk/gtk.h>

static void before_main_destroy(GtkWidget *widget, gpointer data);

int main(int argc, char *argv[])
{
GtkWidget *window;
GtkWidget *label;

gtk_init (&argc, &argv);

window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
gtk_window_set_title (GTK_WINDOW (window), "This is a window !");
gtk_window_set_resizable (GTK_WINDOW (window), FALSE);
g_signal_connect (G_OBJECT (window), "destroy", G_CALLBACK 
(before_main_destroy), NULL);

label = gtk_label_new ("Brrr");
gtk_container_add (GTK_CONTAINER (window), label);
gtk_widget_show (label);

gtk_widget_show(window);
gdk_window_set_decorations (GDK_WINDOW(window->window), GDK_DECOR_TITLE 
| GDK_DECOR_MENU);
 
gtk_main ();

return 0;
}

static void before_main_destroy(GtkWidget *widget, gpointer data)
{
gtk_main_quit ();
}