I suspect his grasp of the facts is so poor that he really has none in mind.
I'm not Catholic so I don't give a rats ass which pope Pius it was.
Then it's kind of odd that you are so overly concerned about what Pope Benedict has to say.
I would hope every thinking person would give considerably more than a rat's ass about the truth, however.
So, since it hasn't been mentioned by others, I would point out that the Chief Rabbi of Rome, Emile Zolli, converted to Catholicism after the end of WWII, and took Eugenio as his baptismal name. Pope Pius XII's given name was Eugenio Pacelli, so there you have objective evidence that a prominent Jew in a position of authority found Pope Pius XII's actions with regard to the Jews inspirational.
Nor was Zolli's conversion merely symbolic sentimentality. He went on to write a theological reflection on Jesus Christ, entitled The Nazarean. Naturally, he had to sacrifice his position as Chief Rabbi to do this. But that was not all his conversion cost him: he died in poverty and obscurity, when he could have had a measure of prominence and financial comfort.
Pius XII exhausted his personal fortune (his family was wealthy) ransoming Jews by obtaining gold which the Nazis demanded. He also hid a number of Jewish families in the papal summer residence at Castel Gandolfo.
Not only were there many examples of Catholic heroism in resisting Naziism and protecting Jews from the Final Solution, those examples extended to the Pope himself. While Cdl. Pacelli was nuncio (ambassador) in Berlin, his predecessor, Pius XI, issued the letter Mit Brennende Sorge (With Burning Anxiety) to the Catholic parishes in Germany, warning them of the dangers of Naziism. Cdl. Pacelli is known to have contributed substantially to the contents of that letter.
Perhaps more could have been done, but it must be recalled that the Vatican City State was surrounded at the time on all sides by fascist Italy, which was allied with Nazi Germany. Musolini could have ordered an invasion at any time, and the only forces the Vatican could have resisted with were about 150 Swiss Guards. It is also true that a strong public denunciation issued by the Dutch bishops provoked a brutal retaliation by the Nazis on a number of innocent people. Therefore, a nuanced, diplomatic public stance was required to avoid even more atrocities.
The apology issued by Pope John Paul II has been spun in the anti-Catholic mainstream media (which opposes the Catholic Church for its moral stances, primarily on sexual issues), but one must read his actual statement to find the truth. (The antidote to propaganda is always to go to original, rather than secondary sources.) It is certainly true that some Catholics have in the past adopted anti-Semitic attitudes and acted on them, but that was never in conformance with Church teaching. (The Vatican II document Nostra Aetate is not a departure from past teaching, as certain people would have you believe, but a restatement and amplification of the Catholic Church's authentic tradition.) Pope John Paul was apologizing for the failures of individual Catholics to live up to the demands of our faith.