Quicksilver Plugin Question

[jp63]

Hi

I'm writing my first quicksilver plugin and I was wondering if the
following is acceptable:

// iTunesModuleSource.m

- (NSArray *) objectsForEntry:(NSDictionary *)theEntry{
    ....
    // Get last modified date of iTunes library.
    NSError *err = nil;
    NSDictionary *xmlAttributes = [[ NSFileManager defaultManager ]
attributesOfItemAtPath:location error:&err ];
    if ( err) {
        [ theEntry setValue:@"Error retrieving last modified date of
iTunes library." forKey:NSFileModificationDate ];// Can i do this???
    }
    else {
        [ theEntry setValue:[ xmlAttributes
objectForKey:NSFileModificationDate ]
forKey:NSFileModificationDate ];// Can i do this???
    }
}

Is it okay for me to add a value to theEntry for the key
NSFileModificationDate? In indexIsValidFromDate:forEntry:, I test to
see if the iTunes library has been modified since the last time it's
been read.

Thanks ahead of time!