Strictly speaking, the Address Book in OS X is a completely separate program from Mail. The Address Book is accessible from many other programs, other than mail, on a sort of system wide basis.
In its latest version, 4.0.2, it is capable of importing a number of common address formats and, fortunately, a text file. I believe it could do this in earlier versions but not too far back. Panther should be OK.
Now, if you can export your address book from OE 5.0 into a text file, you can move that file to the OS X machine and import it into the Address Book.
Does this help?
P
CAN I IMPORT THE ADDRESSES FROM OE 5.0 TO THE ADDRESS BOOK IN MAIL -- THE OE DATABASE DOES NOT SEEM TO FIT THE FILE TYPE NEEDED. A WORK-AROUND??

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