Does an undef symbol from a vtable implicate and error between interface and implemenation?

Does this kind of error implicate an error between an interface and its implementation?

Undefined symbols for architecture i386:
  "MyClass::ChangeManager::GetChanges(
       MyClass::ObjectId, 
       MyClass::IChangeManager::Changes&, 
       bool)"
  , referenced from:
  vtable for MyClass::ChangeManager in libMobileUtils.a(ChangeManager.o)