diff --git a/buildbot/master.cfg b/buildbot/master.cfg
index 29f974d0..21c39abe 100644
--- a/buildbot/master.cfg
+++ b/buildbot/master.cfg
@@ -190,7 +190,7 @@ def makeFactory(port, buildType='buildOnly', pyVer='2.7'):
         if buildType == 'dist':
             cmd += ' bdist_egg --upload'
         
-    cmd = cmd.split() + [Property('buildargs')]
+    cmd = cmd.split() + [Property('buildargs', default='')]
     factory.addStep(ShellCommand(command=cmd, workdir="Phoenix", 
                                  description="building", descriptionDone="build"))
     return factory