Continuing from this post, I found the following in R. Yitzhak Herzog's Judaism: Law & Ethics, pp. 200-202:
A certain Aggadah originally due to Bar-Kappara interprets in this connection Gen. 9:27 as predicting that the beauty of Japhet (the beautiful idiom of Hellas) would one day take up its abode in the tents of Shem... An old extra-Talmudic source -- Megillat Ta'anit -- strikes a somewhat different note. The eighth of Tebet, the day on which the Torah was translated into Greek, or rather on which the completion of the translation took place, in the reign of King Ptolemy is therein marked as a fast day: darkness came at that time upon the world for three day. Soferim 1:7 (35a) echoes the same sentiment in stating that the day on which the Torah was first rendered into Greek was as sad for Israel as that on which the golden calf was made, "because the Torah could not be adequately translated"...
Soferim, in fact, gives the impression of an attempt at harmonising conflicting traditions. Chapter 1:7, the passage just cited, speaks of a pre-Septuagint translation made for Ptolemy by five elders, while the paragraph immediately following refers, in terms practically identical with the Talmudic account to a second translation likewise written for Ptolemy by seventy-two elders...
The first impulse of the faithful watchmen of Zion would not improbably prompt them to an outburst of antagonism to so unprecedented a departure in the inner development of Jewish life. They would view with alarm the raising of a rival to the original text. Their apprehensions would be grounded upon a variety of considerations. Might not the Greek translation entirely supersede, in the course of time, the original Torah in those countries where the Greek language and Greek culture predominated?... Was it at all possible to produce a translation of the Torah that would fully represent the original? Was not the oral law indissoluble bound up with the Hebrew text, and would not the exclusive use of the Greek text by a considerable section of Jews lead to their alienation in spirit and practice from the oral Torah? What guarantee was there that the Greek version would not, in the process of time, suffer alteration and interpolation?
Side by side, however, with such forebodings and misgivings, justified in fact to a considerable extent by subsequent developments, a certain feeling would gradually assert itself which would take a pride in the fact that by means of the Septuagint the sublime truths of Judaism and the origins and early history of Israel had been made known to the outside world. The Mishnah asserts that the Torah was originally written not only in Hebrew, but in all the languages spoken at the time of the giving of the Law. Rabbi Simeon declares that the Torah was written in all languages to enable the contemporary nations to learn its contents. The sentiment underlying these assertions may very well have animated many a Palestinian teacher at a much earlier period and have brought about a certain modification of attitude with regard to the literary event "which happened under King Ptolemy."