Midi Clock on 2 different Computers?-In theory!

[TREATMENT]

Hey guys, new to this can't find info ANYWHERE:

(Macbook Pro 2.4 Duo2Core, OS 10.5.8), Mac Mini, same specs, OS 10.6.6)
I am using one computer for Ableton Live, sending beat clock on the IAC bus.
I've read the manual for syncing Ableton to Resolume, and I get it, and I can do it.
ON ONE COMPUTER!

Now, I have googled sending MIDI over the network via an Ethernet cable, and I am so close....yet...
I get this error message:

"0.0.0.0:5016 "(my laptop)" didn't respond to the connection request.
Check the address and port, and any firewall or router settings
(17:42:26)

Far from being a Network/Internet genius, I googled the error message which didn't get me very far.
NO IDEA how to check my Firewall settings, and don't uderstand SQUAT about my network settings in the first place.

Anyone had this message, or know how to get around it?

Any help MUCH appreciated, this is the ONE things stopping me from performing live....

Cheers
TREATMENT

[Tschoepler]

0.0.0.0:5016 < this is no regular IP for networking. what router/hub is in use? what is the ip-range? what is the ip of the two macs? are they connected via lan or wlan? is little snitch or another software firewall active on either one of the machines? what are the settings in live an avenue? maybe upload some screenshots. makes things easier.