diff -rup xen-3.1.0-src.orig/tools/python/xen/xend/server/netif.py xen-3.1.0-src.new/tools/python/xen/xend/server/netif.py

--- xen-3.1.0-src.orig/tools/python/xen/xend/server/netif.py	2007-09-19 14:24:34.000000000 -0400

+++ xen-3.1.0-src.new/tools/python/xen/xend/server/netif.py	2007-09-19 14:25:28.000000000 -0400

@@ -108,17 +108,15 @@ class NetifController(DevController):

         ipaddr  = config.get('ip')

         model   = config.get('model')

-        if not typ:

-            typ = xoptions.netback_type

-

         if not mac:

             mac = randomMAC()

         devid = self.allocateDeviceID()

         back = { 'script' : script,

-                 'mac'    : mac,

-                 'type'   : typ }

+                 'mac'    : mac }

+        if typ:

+            back['type'] = typ

         if ipaddr:

             back['ip'] = ipaddr

         if bridge: