Ical: emails disappear

[stax]

After my last synchronization between Ical and my mobile phote (Motorola Razor), in which I had chosen to synchonize only the phone numbers and the calendar, all the email adresses from Ical have disappeared. To be more specific, all the email adresses from the contacts whose phone number I already had on my mobile. Can someone explain what happened and most important, how to find those emails again. I have luckily made a back up of my adress book one week prior to this catastrophy.
Thanks