Choose path of Path Cell in NSTableView?

Question

I've added a NSPathCell to a table view:

- (void)awakeFromNib {
 NSPathCell *pathCell = [[[NSPathCell alloc] init] autorelease];
 [pathCell setPathStyle:NSPathStylePopUp];
 [pathCell setControlSize:NSSmallControlSize];
 [pathCell setAllowedTypes:[NSArray arrayWithObject:@"public.folder"]];
 [[tableView tableColumnWithIdentifier:@"destination"] setDataCell:pathCell];
}

The array controller connected to the table column provides an array of NSURL objects. Up to this point everything works fine, but if I try to edit a path using the built in "Choose..." button, nothing changes. (The Open-Dialog appears but after clicking "OK" it's still showing the old path) How can I fix this problem?