Illegally mutated the NSFetchedResultsController's fetch request

I'm getting the following exception is thrown under iOS 4.0 but not under 3.0 using core data. I'm populating a tableview controller with data from a core data store. Then drilling do开发者_开发知识库wn on a row and requesting the details for that row and passing them onto a detail view.

FATAL ERROR: The persistent cache of section information does not match the current configuration. You have illegally mutated the NSFetchedResultsController's fetch request, its predicate, or its sort descriptor without either disabling caching or using +deleteCacheWithName:

Try disabling caching. When you create the NSFetchedResultsController, pass nil as the cache name.

myFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest managedObjectContext:context sectionNameKeyPath:sectionNameKeyPath cacheName:nil];