OS: Vista

I have been using Windows Mail and Windows Contact as my email and contact
programs. I have just installed Office 2007 and want to replace Mail and
Contact by Outlook. However, when I tried to import my contacts into
Outlook, I find that some fields are missing:

Birthday
Anniversary
Spouse/Partner
Children

I see that there are fields for Birthday and Spouse/Partner in Outlook but
the data has not been imported. As for Anniversay and Children, I can't find
these fields in Outlook.

What can I do to make sure that all these fields are properly imported?

Thanks!