Collection->afterFetch() is not imlemented. What to use instead?

Hi,

I have a few collections and could not find any method to implement the PHP's __construct() behaviour. the initialize() is for once-per-request (with no data in it), the onConstruct() if for on construct, but I cannot access data - it runs before putting data into the collection... For models there is: afterFetch() - beforeSave() methods to initialize proptery values for using them and resetting before saving. What can I use for collections?

Thanks, TeeCee :o)