P.S. Before installing it is worth selecting all your address book
entries and "Export vcard". Comparing the 10.3 vs 10.4 "~/Library/
Application Support/AddressBook" directories reveals some different
file naming protocols. Updating the new address book was not a simple
case of copying over 10.3 files to this location (although to be
honest, I avoided renaming my 10.3 files to those of 10.4. I was
unsure whether new archiving methods are in place for 10.4 databases,
given the advent of Spotlight). Importing vcards was the method I
had to choose to update my address book, so ensuring your old address
book is archived in this format prior to 10.4 installation might be a
handy tip.
I should also add I performed a clean install. Such problems may not
exist doing an upgrade installation.
Cheers, Matt