Correct me if I'm wrong but the Ecumenical Synods are infallible, right?
And the Eastern "Orthodox" church accepts their infallibility, right?EXTRACTS FROM THE ACTS. SESSION II.
[immediately following the above-cited letter of the Pope to the Synod of Ephesus]
Philip the presbyter and legate of the Apostolic See said: There is no doubt, and in fact it has been known in all ages, that the holy and most blessed Peter, prince (exarkoV) and head of the Apostles, pillar of the faith, and foundation (qemelioV) of the Catholic Church, received the keys of the kingdom from our Lord Jesus Christ, the Saviour and Redeemer of the human race, and that to him was given the power of loosing and binding sins: who down even to to-day and forever both lives and judges in his successors. The holy and most blessed pope Coelestine, according to due order, is his successor and holds his place, and us he sent to supply his place in this holy synod, which the most humane and Christian Emperors have commanded to assemble, bearing in mind and continually watching over the Catholic faith. Council of Chalcedon, 451
[EXTRACTS FROM THE ACTS. SESSION I.]
Paschasinus, the most reverend bishop and legate of the Apostolic See, stood up in the midst with his most reverend colleagues and said: We received directions at the hands of the most blessed and apostolic bishop of the Roman city, which is the head of all the churches, which directions say that Dioscorus is not to be allowed a seat in this assembly, but that if he should attempt to take his seat he is to be cast out. This instruction we must carry out; if now your holiness so commands let him be expelled or else we leave.
Lucentius, the most reverend bishop having the place of the Apostolic See, said: ... And he [Dioscorus] dared to hold a synod without the authority of the Apostolic See, a thing which had never taken place nor can take place.
Paschasinus the most reverend bishop, holding the place of the Apostolic See said: We cannot go counter to the decrees of the most blessed and apostolic bishop ["Pope" for "bishop" in the Latin], who governs the Apostolic See, nor against the ecclesiastical canons nor the patristic traditions.
Lucentius, the most reverend bishop, and legate of the Apostolic See, said: Since the faith of Flavian of blessed memory agrees with the Apostolic See and the tradition of the fathers it is just that the sentence by which he was condemned by the heretics should be turned back upon them by this most holy synod. THE TOME OF ST. LEO.
Whereupon the blessed Peter, as inspired by God, and about to benefit all nations by his confession, said, "Thou art the Christ, the Son of the living God." Not undeservedly, therefore, was he pronounced blessed by the Lord, and derived from the original Rock that solidity which belonged both to his virtue and to his name, who through revelation from the Father confessed the selfsame to be both the Son of God and the Christ EXTRACTS FROM THE ACTS. SESSION II. (continued).
After the reading of the foregoing epistle [the Tome of Leo], the most reverend bishops cried out: This is the faith of the fathers, this is the faith of the Apostles. So we all believe, thus the orthodox believe. Anathema to him who does not thus believe. Peter has spoken thus through Leo. So taught the Apostles. Piously and truly did Leo teach, so taught Cyril. Everlasting be the memory of Cyril. Leo and Cyril taught the same thing, anathema to him who does not so believe. This is the true faith. Those of us who are orthodox thus believe. This is the faith of the fathers. Why were not these things read at Ephesus [i.e. at the heretical synod held there] ? These are the things Dioscorus hid away. EXTRACTS FROM THE ACTS. SESSION IV.
Paschasinus and Lucentius, the most reverend bishops, and Boniface the most reverend presbyter, legates of the Apostolic See through that most reverend man, bishop Paschasinus said: ... And in the third place the writings of that blessed man, [Pope] Leo, Archbishop of all the churches, who condemned the heresy of Nestorius and Eutyches, shew what the true faith is. EXTRACTS FROM THE ACTS. SESSION VI.
Lucentius, the bishop, said: The Apostolic See gave orders that all things should be done in our presence [This sentence reads in the Latin: The Apostolic See ought not to be humiliated in our presence. ]; and therefore whatever yesterday was done to the prejudice of the canons during our absence, we beseech your highness to command to be rescinded. But if not, let our opposition be placed in the minutes, and pray let us know clearly [Lat. that we may know] what we are to report to that most apostolic bishop who is the ruler of the whole church [i.e. the Pope], so that he may be able to take action with regard to the indignity done to his See and to the setting at naught of the canons. Fifth Ecumenical Council: Constantinople II, 553 EXTRACTS FROM THE ACTS. SESSION VII.
But we, bishops, answered him [Pope Vigilius]: "If your blessedness is willing to meet together with us and the most holy Patriarchs, and the most religious bishops, and to treat of the Three Chapters and to give, in unison with us all, a suitable form of the orthodox faith, as the Holy Apostles and the holy Fathers and the four Councils have done, we will hold thee as our head, as a [father] and primate...."
And I have found a lot more at: http://www.globalserve.net/~bumblebee/ecclesia/ecu.htm