USB Debugging Already ENABLED but MAC still does not detect it

Hi all,

I'm trying to install a APK into my Samsung Note 2.
This Samsung Note 2 of mine, I have gotten unlocked.
It was originally locked by AT&T.
The first time I tried to get it unlocked by someone, it was unsuccessful.
The 2nd time it was successful.
I haven't tried to use the device for development before it was unlocked before so I do not know if unlocking made the difference or not.

In any case, my problem right now is that I DEFINITELY have USB-DEBUGGING ENABLED in my Settings, and the USB cable is attached properly in both the device and my MAC Book Pro. However, the MAC can't detect it for some reason.

I've used Eclipse to detect it, and it does not detect it.

I tried SnapPea Installer and it also keeps on asking for the device to be connected (even though it already is, which means it doesn't detect it).

I've typed 'adb devices' on the command-line as well and it shows an empty list.

I've also installed Kies and restarted the computer and tried to detect the device but it does not detect it.

How do I solve this problem???

Please help....
Thank you very much in advance