Previously, in rails 2.3.8 i used the prototype-helpers `link_to_remote` and `form_remote_for` (amongst others). 

These had the option `:update` as follows:

```
link_to_remote "Add to cart",
  :url => { :action => "add", :id => product.id },
  :update => { :success => "cart", :failure => "error" }

```

(an example from the [documentation](http://api.rubyonrails.org/classes/ActionView/Helpers/PrototypeHelper.html)).
This example would, upon success update the html-element with class "cart", and upon failure the class "error".

Now i believe the modus operandi has changed, instead we write:

```
link_to "Add to cart", :url => {:action => "add", :id => product.id}, 
    :remote => true

```

and there is no option to set `:update` anymore.
Instead of a normal html, we now render javascript, like this (in jquery) :

```
$('.cart').replaceWith(<%= escape_javascript(render :partial => 'cart') %>)

```

but how do you handle an error situation?
Do i handle it in my controller, and use seperate views?

It would seem useful to me to somehow be able to mimic the behaviour we had before. Any ideas?