As has been pointed out, Fr. Cantalamessa is CONTRADICTING the teaching of Popes John Paul II and Benedict XVI in the Catechism of the Catholic Church. The Catechism teaches that all men are conceived with the stain of Original Sin and that baptism is necessary for salvation. Fr. Cantalamessa is ambiguous on original sin (he calls it an Augustinian doctrine abandoned by the Church? huh?) and claims that baptism is only the ordinary means of salvation, not a necessary means of salvation. The Catechism teaches that it's urgent to baptize infants for the remission of sins: Fr. Cantalamessa teaches that all unbaptized little children go to heaven if they die, and if anyone says otherwise he's contradicting Scripture!
Following St. Paul, the Church has always taught that the overwhelming misery which oppresses men and their inclination towards evil and death cannot be understood apart from their connection with Adam's sin and the fact that he has transmitted to us a sin with which we are all born afflicted, a sin which is the "death of the soul". Because of this certainty of faith, the Church baptizes for the remission of sins even tiny infants who have not committed personal sin. [. . .]The Lord himself affirms that Baptism is necessary for salvation. He also commands his disciples to proclaim the Gospel to all nations and to baptize them. Baptism is necessary for salvation for those to whom the Gospel has been proclaimed and who have had the possibility of asking for this sacrament. The Church does not know of any means other than Baptism that assures entry into eternal beatitude; this is why she takes care not to neglect the mission she has received from the Lord to see that all who can be baptized are "reborn of water and the Spirit." God has bound salvation to the sacrament of Baptism, but he himself is not bound by his sacraments. [A discussion of baptism of desire and baptism of blood follows . . .]
As regards children who have died without Baptism, the Church can only entrust them to the mercy of God, as she does in her funeral rites for them. Indeed, the great mercy of God who desires that all men should be saved, and Jesus' tenderness toward children which caused him to say: "Let the children come to me, do not hinder them," allow us to hope that there is a way of salvation for children who have died without Baptism. All the more urgent is the Church's call not to prevent little children coming to Christ through the gift of holy Baptism.
This is not what Fr. Cantalamessa is saying.
* Fr. C references limbo, not original sin