[IBGregR]

The only time I saw that happen is when I tried to restore my contacts via PIMBackup (or whatever it is called) and then let my phone sync with our exchange server. In my case it doubled them on the phone AND the exchange server so I just used Outlook to delete the duplicates as it is easier than trying to do it on the phone. Unfortunately, once they are there...they are there and you will have to delete them manually.