Syncing OS X Notes with iCloud
Notes in Mac OS and iOS are still based on IMAP email. When you try to set up iCloud notes sync for the first time without having an iCloud email address, you’re forced to create one. I had this experience at last in Mac OS 10.8.4.

Ask your IT staff to open ports for IMAP email which are usually 25, 143, 587, 993.
Hope that helps.