Is this true? Then does it mean that BOD is currently not de fidei?[/color]
Of course it's not de fide. It's not even a real teaching at all, but an error that has grown out of proportion because of one self-contradictory statement of St. Augustine and another self-contradictory statement by St. Ambrose. That's where this whole thing comes from. NOT from Apostolic Tradition or the Deposit of Faith.
St. Augustine said "considering this over and over again", meaning BOD. If BOD is "unanimous Church teaching", what's there to "consider over and over" again? He wasn't even sure about it. The only time he ever taught it he used the Good Thief as evidence to support it, but later on he refuted what he himself had said about the good thief; he later said the good thief may have been baptized after all.
As for St. Ambrose, all there is is his funeral speech, and it's ambiguous at best and he even contradicts BOD in that very same speech!
Then out of nowhere, St. Thomas comes and gives BOD/BOB formal definitions (using St. Augustine and Ambrose as support) and voila, from then on they took off and every other theologian just refined the definition to make it look more professional and sophisticated and gave it his own "theological note".
That's another thing: theologians aren't even sure what this thing is. Some say de fide, others close to the faith, others certain, etc. Some "unanimous and universal teaching of the Church" indeed.
This whole thing is a tower of sand and a doctrine of man.