What is the meaning of "Gam Chamas Tigbal Bah"?
Rashi: Its border will reach the border of Yerushalayim.
Radak: Even though Chamas was a great city - it is called "Chamas Rabah" (Amos 6:2) - and it is outside Eretz Yisrael, for it is one of the borders, then it will be in the border. Also Tzor and Tzidon, which are closer to Yisrael than Chamas, will be in Yisrael's border. Malbim - this is explained in Yechezkel 47:15-17.
Why does it say "Tzor v'Tzidon Ki Chochmah Me'od"?
Rashi: Also they are [Yerushalayim's] daughters, even though they became very wise, and thought to be a mistress in Chochmah.
Radak: Tzor was wise in its own eyes in the old days, and its Chochmah did not help it. However, in the days of Mashi'ach, it will not rely on its Chochmah, and it will be submissive in front of Yisrael.
Radak (5): This is connected to the coming verse. Tzor and Tzidon will think to stand against Yisrael, for [Tzor] was very wise in its own eyes, like it says in Yechezkel (Perek 28). Tzidon was near Tzor, and was drawn after it.
