Q: Shared Calendar on iPhone Calendar

I know that you can do this with iCloud, but this case the shared calendars are from Microsoft Exchange Calendars.  I know you can set this type of calendar up in the Cal app on OSX 10.8, but not sure if and/or how this can be done in the iPhone. 

Thanks

Setting up the Exchage calendar as you indicate does not let you add shared calendars to the iOS device.  Am still looking for how this can be done as it is allowed in OSX.

Thanks ckuan for the assitance!