It's actually more ancient if you consider the fact that the ActiveRecord pattern (in spirit, not in name) goes back to VB3.
I think somewhere in that book (Forewords or preface or whatnot) he also mentioned DHH's help/contribution to the book.
As much as Rails community hates Enterprise, lots of patterns that Rails was built upon showed up in that book as gulp "Enterprise" patterns gulp
It's actually more ancient if you consider the fact that the ActiveRecord pattern (in spirit, not in name) goes back to VB3.