Contacts created on my iPhone won't sync anymore (iOS 6 & 10.6.8)

Hi,

Contacts created on my iPhone don't sync with Mac (= are not visible in Address Book).

I have this problem since I made the iOS 6 update (iPhone 4 / iOS 6.1.2 / Mac OS 10.6.8 / iTunes 11.0.2 / USB sync).

I tried disabling / enabling Contacts sync in iTunes. No effect.

Using iCloud and/or upgrading to Lion is not a solution for me.

Haven't found any solution yet. Others have the same issue:

https://discussions.apple.com/thread/4532995

https://discussions.apple.com/thread/4551925?answerId=21481733022#21481733022

The only clue I've got is the following: using a freeware to backup my phone contacts (by searching in the backup file of the phone created by iTunes), I noticed that the freeware finds the same number of contacts (856) on my phone that Address Book displays on the Mac — yet the iPhone should have 2 more (or the mac 2 less), since I created 2 contacts on the phone that don't display on the mac. So maybe, just maybe, it's a "visibility attribute" problem? I'm not technician.

This issue is very irritating, basically there's no "synchronization" per se anymore.

Thanks in adavance for any help you may provide.

Giu_