How is the "perpetual" excommunication of Acacius by Felix III currently understood in Catholicism?

Around AD 485, the patriarch of Constantinople, [Acacius](https://en.wikipedia.org/wiki/Acacius_of_Constantinople) , was excommunicated by [Pope Felix III](https://en.wikipedia.org/wiki/Pope_Felix_III) , in a dispute over both theology and authority. This excommunication, however, seems unique in that it was said to be "perpetual," as the *Catholic Encyclopedia* explains: > Acacius was branded by Pope Felix as one who had sinned against the Holy Ghost and apostolic authority (*Habe ergo cum his . . . portionem S. Spiritus judicio et apostolica auctoritate damnatus*); and he was declared to be perpetually excommunicate — *nunquamque anathematis vinculis exuendus*. ([source](http://www.newadvent.org/cathen/01082a.htm)) Wikipedia further indicates that Acacius was "irrevocably excommunicated," though I'm not sure if that's an accurate characterization, particularly in light of the [*Catholic Encyclopedia*'s article on excommunication](http://www.newadvent.org/cathen/05678a.htm) , which does not seem to address the concept of a "perpetual" excommunication. After reviewing that article, I can conceive of a few ways that the perpetual excommunication of Acacius could be understood: 1. That this excommunication was simply a "reserved" excommunication, one that could only be absolved by the Pope, and the "perpetual" was an indication of the Pope's confidence that absolution would not be sought or given. 2. That this excommunication was of a special category not described in the *CE*, and that it truly was irrevocable, without any possibility of absolution. - If so, does this special category continue to exist today? 3. That Wikipedia and I misunderstand the term "perpetual" in this context and thus this isn't actually any different from many other excommunications (perhaps the adjective simply means "perpetual until absolution") **How does Catholicism today understand this excommunication of Acacius by Pope Felix?** Was it truly "irrevocable," and if so, can such excommunications be pronounced today?