There are at least three ways you can make this work:

• You could use a Travel Agent like KZBrian said, and keep your v-brakes.
• You could replace the v-brakes with cantilever brakes, which use the same mounting posts as v-brakes and have a similar cable pull to calipers.
• You could replace the v-brakes with mini-v's, which use a similar cable pull to calipers or cantilevers.

All three methods should work well. Personally, I'd probably pick up some Tektro CR720 cantilever brakes. They're cheap and they're easy to set up. I've got CR720's paired with some Sora 3300 brifters and they work very well.