diff -ru xen-3.0.0/tools/examples/network-bridge xen-3.0.0-new/tools/examples/network-bridge
--- xen-3.0.0/tools/examples/network-bridge	2006-01-25 15:30:13.000000000 -0500
+++ xen-3.0.0-new/tools/examples/network-bridge	2006-01-31 12:20:25.000000000 -0500
@@ -61,6 +61,7 @@
 
 vifnum=${vifnum:-0}
 bridge=${bridge:-xenbr${vifnum}}
+netdev=${netdev:-$(ip route list default scope global| awk '{ print $NF }')}
 netdev=${netdev:-eth${vifnum}}
 antispoof=${antispoof:-no}
 
diff -ru xen-3.0.0/tools/examples/xend-config.sxp xen-3.0.0-new/tools/examples/xend-config.sxp
--- xen-3.0.0/tools/examples/xend-config.sxp	2006-01-31 12:23:38.000000000 -0500
+++ xen-3.0.0-new/tools/examples/xend-config.sxp	2006-01-31 12:24:44.000000000 -0500
@@ -70,8 +70,8 @@
 #
 # (network-script network-bridge)
 #
-# Your eth0 is used as the outgoing interface, by default.  To use a different
-# one (e.g. eth1) use
+# Your default ethernet device is used as the outgoing interface, by default. 
+# To use a different one (e.g. eth1) use
 #
 # (network-script 'network-bridge netdev=eth1')
 #
diff -ru xen-3.0.0/tools/examples/xend-config.sxp.mem-min xen-3.0.0-new/tools/examples/xend-config.sxp.mem-min
--- xen-3.0.0/tools/examples/xend-config.sxp.mem-min	2006-01-06 17:42:59.000000000 -0500
+++ xen-3.0.0-new/tools/examples/xend-config.sxp.mem-min	2006-01-31 12:25:13.000000000 -0500
@@ -70,8 +70,8 @@
 #
 # (network-script network-bridge)
 #
-# Your eth0 is used as the outgoing interface, by default.  To use a different
-# one (e.g. eth1) use
+# Your default ethernet device is used as the outgoing interface, by default.
+# To use a different one (e.g. eth1) use
 #
 # (network-script 'network-bridge netdev=eth1')
 #