Something

if (f->flags & RULE_CONTEXT_THREADING) {
		const char *thread_types[] = { N_("_None"), N_("_All related"), N_("Replie_s"), N_("Rep_lies and parents"), N_("No r_eply or parent") };

		label = gtk_label_new_with_mnemonic (_("I_nclude threads"));
		menu = gtk_menu_new ();
	
		for (i=0;i<5;i++) {
			item = gtk_menu_item_new_with_mnemonic(_(thread_types[i]));
			gtk_menu_shell_append (GTK_MENU_SHELL (menu),item);
			gtk_widget_show (item);
		}


		omenu = gtk_option_menu_new ();
		gtk_label_set_mnemonic_widget ((GtkLabel *)label, omenu);
                gtk_label_set_mnemonic_widget((GtkLabel *)item,omenu);
		gtk_option_menu_set_menu (GTK_OPTION_MENU (omenu), menu);
		gtk_option_menu_set_history (GTK_OPTION_MENU (omenu), fr->threading);
		gtk_widget_show (omenu);