If you create an install class which sets up some firewall rules, you can't
then skip the firewall config screen for the gui install because getNext()
doesn't do a sanity check for if it's values have been set.  Not a problem
with gui or kickstart.  Following patch fixes gui

--- anaconda/iw/firewall_gui.py~	Wed Jan 24 02:40:23 2001
+++ anaconda/anaconda/iw/firewall_gui.py	Mon Jan 29 20:09:12 2001
@@ -20,6 +20,9 @@
 #
	dev.set (("onboot", "yes"))

     def getNext (self):
+
if not self.__dict__.has_key("radio3"):
+
	return None
+
 #        print self.ports.get_text ()

         if self.radio3.get_active ():