diff --git a/uncloud/hack/vm.py b/uncloud/hack/vm.py
index 4caa2fe..8d7116c 100755
--- a/uncloud/hack/vm.py
+++ b/uncloud/hack/vm.py
@@ -82,7 +82,7 @@ class VM(object):
         self.mac=MAC(self.config)
         self.mac.create()
         self.vm['mac'] = self.mac
-        self.vm['ifname'] = "uc{}".format(self.mac.to_str_format())
+        self.vm['ifname'] = "uc{}".format(self.mac.__repr__())
 
         # FIXME: TODO: turn this into a string and THEN
         # .split() it later -- easier for using .format()