Hmmm... This is as close as I've come to a clue yet: I used strings to look at the bundle (OS X version of a .so) and found this: %s::%s XS_VERSION VERSION 0.03 %s object version %s does not match %s%s%s%s %_ But doing the same thing on the DBI bundle shows this: %s::%s XS_VERSION VERSION %s object version %s does not match %s%s%s%s %_ So where is the version number in the DBI? The mystery deepens... More digging for me. :-/ Thanks for the clue.