Only sort of. DateTime.pm was originally based on Date::ICal, but the project as a whole has mostly ended up recreating everything ever other date module has ever done.

The problem was that there was lots of functionality in many distros, all with radically different APIs. I suppose we could've just written the mother of all wrapping layers, but I think overall it was easier to just write most things from scratch. This also required even less buy-in or cooperation from authors of the existing modules at the time.