iPhone 3Gs contacts issue

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This is something I just noticed this weekend, let me know if anyone else has/had this problem and how they solved it.

This is all the information I can say for sure:

I noticed this problem after installing iOS4

I am able to add new contacts to my phone, but after I add them I can't delete or edit them in anyway.

Older contacts I had on my phone I can still delete and edit.

I had my phone jailbroken previously, but had to do a restore to it, which updated the phone to 3.1.3 at the time so I didn't jailbreak again. I can't say for sure if I had added any contacts in from the time I did the restore to when I installed iOS4.

 

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After restarting the phone, messing with my contacts settings, and removing my japanese keyboard (adding a funky keyboard allows you to have a custom dictionary, don't know why this would mess up my contacts, but removed it just to be safe), the new contacts that I had added to my phone had mysteriously disappeared and when I readded one of them it came up with that new Linked Cards feature that apple has implemented.

It seems that I was somehow was adding the contact to my exchange contacts but not to the iPhone itself?

Not really sure I did it, but I'm satisfied that it is now "fixed"

If anyone can explain this odd behavior I would be greatly appreciative.