http://revach.net/article.php?id=3189

Section: Parshas HaShavua   Category: Medrash
Parshas VaYigash: Chidushei HaRim - Second Time Around For Yehuda, Shimon, and Yosef
One day, three great tana'im were discussing the Roman contribution to Eretz Yisrael (Shabbos 33b).  Rebbi Yehuda praised their contribution in making marketplaces, bridges, and bath houses.  Rebbi Yosi sat there and didn't comment.  Rebbi Shimon said that everything they did, they did only for themselves, in detriment to the Jews.  When the Romans heard about this conversation, Rebbi Yehuda was made the leader and chief Jewish spokesman, Rebbi Yosi was sent to Galus in Tzipori for remaining quiet, and the Rebbi Shimon was slated to be executed for his slanderous words.  Rebbi Shimon then went into hiding and spent twelve years in a cave.

The Chidushei HaRim explains a Medrash that says that this parallels the plight of the three central players of the same names in Mechiras Yosef: Yehuda, Shimon, and Yosef.  Yehuda who stood up to speak before Yosef in Mitzrayim became the leader.  Yosef who remained quiet when his brothers called Yaakov, "his servant" was sent to Galus.  The galus started because of Tzipori.  Like a bird, Yosef spoke about his brothers more than he should have.  And with a bird a Mitzora purifies himself.  Shimon, who instigated the entire episode in which Yosef was sent to Mitzrayim and spent 12 years in jail, himself spent 12 years in the cave as a kapara.