diff -r 18758847bf31 tools/python/xen/xend/image.py
--- a/tools/python/xen/xend/image.py	Wed Oct 14 09:09:23 2009 +0100
+++ b/tools/python/xen/xend/image.py	Wed Oct 14 12:28:35 2009 -0600
@@ -869,9 +869,14 @@
             ret.append("-net")
             ret.append("nic,vlan=%d,macaddr=%s,model=%s" %
                        (nics, mac, model))
+            vifname = devinfo.get('vifname')
+            if vifname:
+                vifname = "tap-" + vifname
+            else:
+                vifname = "tap%d.%d" % (self.vm.getDomid(), nics-1)
             ret.append("-net")
-            ret.append("tap,vlan=%d,ifname=tap%d.%d,bridge=%s" %
-                       (nics, self.vm.getDomid(), nics-1, bridge))
+            ret.append("tap,vlan=%d,ifname=%s,bridge=%s" %
+                       (nics, vifname, bridge))
 
         if nics == 0:
             ret.append("-net")