Xcode "Undefined symbols for architecture armv7" after attempted iAd script in Unity

So we're a couple of interns that are pretty new to Unity working on a project for awhile, and our company wanted us to add iAd support to our project. After using the following code,

using UnityEngine; using System.Collections; public class AdBanner : MonoBehaviour { private static AdBanner instance = null; private ADBannerView banner = null; public static AdBanner Instance { get { return instance; } } void Awake() { if(instance != null && instance != this) { Destroy(this.gameObject); return; } else { instance = this; } DontDestroyOnLoad(this.gameObject); banner = new ADBannerView(ADBannerView.Type.Banner, ADBannerView.Layout.Top); ADBannerView.onBannerWasLoaded += OnBannerLoaded; } void OnBannerLoaded() { banner.visible = true; } }

we're met with the following error in Xcode, referenced 7 times:

 Undefined symbols for architecture armv7:
   "__StopAdBanner", referenced from:
       RegisterMonoModules() in RegisterMonoModules.o
   "__StartAdBanner", referenced from:
       RegisterMonoModules() in RegisterMonoModules.o
   "__Visible", referenced from:
       RegisterMonoModules() in RegisterMonoModules.o
   "__Height", referenced from:
       RegisterMonoModules() in RegisterMonoModules.o
   "__Width", referenced from:
       RegisterMonoModules() in RegisterMonoModules.o
   "__FullScreen", referenced from:
       RegisterMonoModules() in RegisterMonoModules.o

Naturally we believe this to be the cause of the iAd implementation. We've scoured Google and these very forums for a week looking for an answer, but any suggestions made don't yield any success. Any help or information at all would be greatly appreciated. Will provide more information if needed.