Birthdays of address book accounts others than local

Question

There appear no birthdays in iCal for contacts of Apple's address book, if the contact are NOT within the Local account, but part of a CardDAV account. If I copy a contact to the Local account the birthday appears in iCal.
My iPhone (iOS4) uses also CardDAV to sync these contacts, but the birthdays are shown in the iPhone's calendar perfectly.
Is iCal able to handle birthdays of Local contacts only?

Answer 1

Sorry for the delayed response.  As I said, this is a quick hack of somebody else's work, so the end result isn't pretty, but it works.
http://www.jmatt.net/misc/vbook.php.txt
http://www.jmatt.net/misc/vcard.php.txt
vbook is the script you run.  It requires vcard.
To execute it, first export your address book entries into a single vcf file.  In Address Book, select the server account.  In the menu , select File->Export->Export Group vCard  and put the file wherever you want it.  The script as written expects to find this file in the folder above the script, but that's easy to change.
After you have the file in the right place, execute the script.  It writes to standard output, so you'll probably want to pipe it to an .ics file.  Then import that file into iCal.
As I mentioned, if you have multiple Macs, you'll want to run this file on each one, and import the file into a local calendar.  If you try to put it on a server and share it between Macs, the address book links in the calendar entries won't work.
Obviously, this is a minor PITA as you need to run it regularly if you have a lot of changes in your Address Book.  It's not too bad for me, because I don't have a lot of changing info.  I run it every few months, whenever I think about it, in case I've recently added a birthday to my address book.
I'm hoping that this will all become unnecessary when iCloud rolls out