I recently imported 512 contacts into zimbra's contact manager. Most of them seem to have went well, but some spot checking shows that some email addresses were skipped. Phone numbers and names all seem fine, as do the notes field (although it looks like there might be a pretty tight limit on the length of that).

Here's what I believe the format is that zimbra wants:

"Birthday","Business City","Business Country","Business Fax","Business Phone","Business Phone 2","Business Postal Code","Business State","Business Street","Business Street 2","Business Street 3","Callback","Car Phone","Company","Company Main Phone","Department","E-mail Address","E-mail Display Name","E-mail Type","E-mail 2 Address","E-mail 2 Display Name","E-mail 2 Type","E-mail 3 Address","E-mail 3 Display Name","E-mail 3 Type","First Name","Home City","Home Country","Home Fax","Home Phone","Home Phone 2","Home Postal Code","Home State","Home Street","Home Street 2","Home Street 3","Initials","Job Title","Last Name","Middle Name","Mobile Phone","Notes","Other City","Other Country","Other Fax","Other Phone","Other Postal Code","Other State","Other Street","Other Street 2","Other Street 3","Pager","Suffix","Web Page"
And here's the line that imported but skipped all email fields. Some info has been altered for privacy. Contact me directly for a verbatim copy:

"","","","","408-349-62xx","408-349-62xx","","","","","","","","Yahoo Inc.","408-349-62xx","Changed","changed@yahoo-inc.com","changed@yahoo-inc.com","INTERNET","","","INTERNET","","","","Carlo","","","","","","","","","","","","","C","","","20050408: Spoke to him about our duplicate problem.  Send connecting IP, sample of changed, changed logs.  Mentioned changed going to changed - there's an application for changed which he will point me to.
20051100: email bounced.
20051111: CLM for Changed, hopefully she's in the same dept. or can refer.","","","","","","","","","","","",""