I'm setting up the network renderer for remote rendering as specified in the Blender docs. I have slave and master blend files, and I need to set the master IP to an Amazon EC2 instance, then transfer the file to said instance and start Blender.

The problem is that if I input an IP for the master while the master isn't actually running, Blender freezes, and I'm presented with the spinning beach ball until I kill Blender.

Running Lion 10.7.5, and the official Blender 2.64 build.