hey marcomoreno,
unfortunately haven't found the answer but I seemed to have found a workaround.
I have Protools LE 7.1 also installed and after installing snow leopard I booted it up to see if I experienced the same problem and for some reason the midi works normally. Then I just happened to restart Logic (Whilst Protools was still running) and the midi in Logic also worked fine. Before this Logic wouldn't even boot up, it would hang in the boot sequence when it was "Checking Midi Drivers". So as a work around I bootup the "Digi Core Audio Manager" before I boot Logic and all is fine.
Ironically i have a feeling that Protools might actually be the culprit. I don't have the time to prove it right now, but I have a suspicion that there is some driver clash with Logic. I'd like to uninstall Protools and see what happens.. for now I'm happy to leave it alone.
I'd be interested to know if you have Protools installed as well?
