estou usando xcode 4.5 (4G182) com o iOS 6. NSDateFormatter mostrar ano errado no iOS 6, como resolver?

NSDateFormatter *dateFormatter = [[[NSDateFormatter alloc] init] autorelease];
[dateFormatter setDateFormat:@"YYYY-MM-dd"];
NSString *str = [dateFormatter stringFromDate:[NSDate date]];
NSLog(@"%@ == %@",str,[[dateFormatter dateFromString:str] description]);

imprime "2012-09-14 ==2011-09-13 16:00:00 +0000 "