diff -p -up dhcp-4.1.0p1/client/scripts/linux.mtu dhcp-4.1.0p1/client/scripts/linux
--- dhcp-4.1.0p1/client/scripts/linux.mtu	2010-01-26 10:44:28.000000000 -0200
+++ dhcp-4.1.0p1/client/scripts/linux	2010-01-26 10:45:21.000000000 -0200
@@ -210,6 +210,13 @@ if [ x$reason = xBOUND ] || [ x$reason =
   if [ -n "$METRIC" ]; then
 	ifmetric $interface $METRIC
   fi
+  # set MTU if server specifies one and no MTU is defined in network config
+  if [ -z "$MTU" ]; then
+      if [ -n "$new_interface_mtu" ]; then
+	ifconfig $interface mtu "$new_interface_mtu"
+      fi
+  fi
+
   if [ "${PEERDNS}" != "no" ]; then 
      make_resolv_conf
   fi