data fault

What would cause a fault when fetching an entry?

for example, I'm getting things like this when fetching entries. The first is a normal entry, and the second says data fault.

MIEntryData: 0x4ce5e80 (entity: EntryData; id: 0x4ce5e50 x-coredata://336FF957-BFE1-4E2B-9365-C0AFD2398481/EntryData/p218 ; data: {
GTD = na;
attachmentCount = nil;
characterCount = nil;
checkbox = nil;
comment = nil;
context = nil;
creationDate = 2005-09-07 09:48:09 -0700;
dateDue = 2006-10-02 12:00:00 -0700;
dateLastCompleted = 2006-09-25 11:39:10 -0700;
descendantCount = nil;
dueDate = nil;
encrypted = nil;
entryDataID = 10;
flagged = nil;
hasNoteText = nil;
isFetchRequest = 0;
joinedEntries = (
0x4cb49c0 ,
0x4c1e2d0
);
kind = "com.apple.rtfd";
label = 1;
lead = nil;
locked = nil;
modificationDate = 2006-03-21 15:00:56 -0800;
note = 0x5c53550 x-coredata://336FF957-BFE1-4E2B-9365-C0AFD2398481/Note/p19;
onComplete = "";
paragraphCount = nil;
read = 1;
recur = Mon;
starRating = 2;
tags = "relationship fault: 0x5c537e0 'tags'";
title = "write in lab journal dilligently to better define ";
userInfo = nil;
wordCount = nil;
}),
MIEntryData: 0x5cd0b70 (entity: EntryData; id: 0x5c1cc30 x-coredata://336FF957-BFE1-4E2B-9365-C0AFD2398481/EntryData/p753 ; data: fault)

The code that generates this is:

//check due entries for urgency
predicate = [NSPredicate predicateWithFormat:@"%K != nil", MGdateDueKey];
@try {
[fetchRequest setEntity:[NSEntityDescription entityForName:@"EntryData" inManagedObjectContext:managedObjectContext]];
[fetchRequest setPredicate:predicate];
fetchResults = [managedObjectContext executeFetchRequest:fetchRequest error:&fetchError];
} @catch (NSException *e) {
logErrorWithException(@"failed executeFetchRequest", e);
}
DLog(@"Due Entries: %@", [fetchResults description]);

thanks,
Jeff