actually there's a quicker fix for this. We had 7 Mac laptops linked together via Midi over the Ethernet-Midi network. We performed this 7-laptop scenario in front of audience of 50 people or so, it was an event called Slammo! in Oregon back in September. It worked incredibly well and I hope to get a bunch of musicians together again for an 09 version.

We had a master computer sending midi-out, then his cat-5 cable went into a Linksys 8-port internet router. The router then sent 6 other cables out to our Mac's. Each computer selected Network-Midi as the incoming signal.

In Ableton's preferences menu, under the midi assignment page, you will see a Delay Compensator adjustor for Midi signals. we started with -9 milliseconds and adjusted it from there. This is usually the standard midi latency coming from Ableton. Your master does not need to be adjusted, but all of your slaves do.

Keep playing with this until it's tight. You want to be able to hit Play on the master computer, and have all the others fall in suit. I highly suggest turning on your metronomes on each computer to make sure all is good.

hope this helps!