that's a rather archaic usage of Exporter
How should anyone know better? The documentation of Exporter has not been changed much (diff) in the last six years, all of the problems I wrote about six years ago still exist, starting with the archaic example using require and @ISA = qw(Exporter). Almost all examples still inherit from Exporter, and only half way down through the documentation a single example shows that you don't have to inherit from Exporter. Inheriting from Exporter is still shown as "good practice". Even worse, the documentation shows how to use base or parent to inherit from Exporter. And don't make me think about the recommended Exporter::Easy, hiding the unneeded inheritance in yet another module.
Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)