Can somebody explain why I get "System.EntryPointNotFoundException: ABAddressBookCreateWithOptions"?

EXCEPTION: System.EntryPointNotFoundException: ABAddressBookCreateWithOptions at (wrapper managed-to-native) MonoTouch.AddressBook.ABAddressBook:ABAddressBookCreateWithOptions (intptr,intptr&) at MonoTouch.AddressBook.ABAddressBook.Create (MonoTouch.Foundation.NSError& error) [0x00000] in :0 at Test.Core.MonoTouch.RecipientView.ShowAutocompleteList (System.String sCompareAddress) [0x00000] in :0 at Test.Core.MonoTouch.RecipientView+TextFieldDelegate.ShouldChangeCharacters (MonoTouch.UIKit.UITextField textField, NSRange range, System.String replacementString) [0x00000] in :0 at MonoTouch.UIKit.UIApplication.SendEvent (MonoTouch.UIKit.UIEvent uievent) [0x00000] in :0 at Test.UIApplicationMain.SendEvent (MonoTouch.UIKit.UIEvent oEvent) [0x00000] in :0 at MonoTouch.UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) [0x00000] in :0 at Test.Application.Main (System.String[] args) [0x00000] in :0