I'm trying to use the apprequests dialog to send invites to friends who do not have the app installed yet.

To show only the the friends without the app I'm using the filters param with "app\_non\_users". However it has no affect on the resulting dialog (i get all friends).

This is the code i'm using:

```
SBJSON *jsonWriter = [[SBJSON new] autorelease];

NSArray *filters = [NSArray arrayWithObject:@"app_non_users"];

NSString *filtersString = [jsonWriter stringWithObject:filters];

NSMutableDictionary* params = 
[NSMutableDictionary dictionaryWithObjectsAndKeys:
 @"invites you to check out cool stuff",  @"message",
 @"Check this out", @"notification_text",
 filtersString, @"filters",
 @"Invite Friends", @"title", 
 nil];  

[facebook dialog:@"apprequests"
       andParams:params
     andDelegate:self];

```

What am I missing to get it to work?