The U-Connect function doesn't work on models earlier than '11... maybe '10, I'm not certain on the year. But in my '08 owners manual it states that the U-Connect function is not available on the Wrangler models. The button is there because that deck is used on pretty much every modern Chrysler model.
I have heard of guys buying the equipment needed to get it working. I think you need a microphone and if you have the normal deck instead of the fancy pants touch screen w/nav you need a seperate module too. (The fancy one has the module integrated)
If I remember correctly it is kind of pricey, like $500 for the module and $50 for the mic. Don't take any of this information too seriously, I am totally going off of memory from a thread I read months ago on a different forum.