NSDate appears to leak

FROM : Lloyd Sargent
DATE : Wed Nov 21 19:51:04 2007

I'm trying to track down a problem on 10.4.11 using MallocDebug. When 
I had tested this with 10.4.10 I don't think I had this problem, but 
now I get the following:

(Column-wise going down)

_pthread_body
forkThreadDataForFunction
[Thread3 userThread:]
+[NSDate dateWithTimeIntervalSinceNow:]

This is the code that is causing said leak:

- (void) userThread: (id) param
{
   
    //----- create the autorelease pool so we don't leak
    NSAutoreleasePool *localPool = [[NSAutoreleasePool alloc] init];
   
    sleep(10);
   
    while (1)
    {
          [[NSRunLoop currentRunLoop] runUntilDate: [NSDate 
dateWithTimeIntervalSinceNow: 1]];    
    }
   
    [localPool release];
}

Is NSDate the culprit or is it the fact that NSRunLoop is not thread 
safe?

Or is MallocDebug making me chase my tail?

Thanks for any help on this one!