Check my other posts for more info on this problem.
I finally got it to work after disabling a Vodafone/Huawei driver for a GSM/3G pen that
was making impossible the USB serial port access.
This what I did:
- Uninstalled the program
- In Network preferences I deleted the services associated with the pen
- In System|Library|Extensions I deleted the *.kext files associated with the pen
After a reboot Arduino works!