=== modified file 'src/provisioningserver/utils/__init__.py'
--- src/provisioningserver/utils/__init__.py	2014-03-28 15:23:38 +0000
+++ src/provisioningserver/utils/__init__.py	2014-04-14 22:14:09 +0000
@@ -819,7 +819,7 @@
 
     output = call_capture_and_check(['arp', '-n']).split('\n')
 
-    for line in output:
+    for line in sorted(output):
         columns = line.split()
         if len(columns) == 5 and columns[2] == mac:
             return columns[0]