diff -up system-config-printer-1.2.5/system-config-printer.py.NPTLpdQueue system-config-printer-1.2.5/system-config-printer.py
--- system-config-printer-1.2.5/system-config-printer.py.NPTLpdQueue	2010-10-22 11:18:13.000000000 +0200
+++ system-config-printer-1.2.5/system-config-printer.py	2010-10-22 11:18:13.000000000 +0200
@@ -6083,6 +6083,9 @@ class NewPrinterGUI(GtkGUI):
         self.btnNPTLpdProbe.set_sensitive (len (hostname) > 0)
         self.setNPButtons()
 
+    def on_cmbentNPTLpdQueue_changed(self, cmbent):
+        self.setNPButtons()
+
     def on_btnNPTLpdProbe_clicked(self, button):
         # read hostname, probe, fill printer names
         hostname = self.cmbentNPTLpdHost.get_active_text()
diff -up system-config-printer-1.2.5/ui/NewPrinterWindow.glade.NPTLpdQueue system-config-printer-1.2.5/ui/NewPrinterWindow.glade
--- system-config-printer-1.2.5/ui/NewPrinterWindow.glade.NPTLpdQueue	2010-10-12 18:03:22.000000000 +0200
+++ system-config-printer-1.2.5/ui/NewPrinterWindow.glade	2010-10-22 11:19:51.000000000 +0200
@@ -752,7 +752,7 @@ ipp://printer.mydomain/ipp</property>
                                             <accessibility>
                                               <relation type="labelled-by" target="label201"/>
                                             </accessibility>
-                                            <signal name="changed" handler="on_entNPTDevice_changed"/>
+                                            <signal name="changed" handler="on_cmbentNPTLpdQueue_changed"/>
                                           </object>
                                           <packing>
                                             <property name="left_attach">1</property>