How to send multiple values to controller using :with option of collection_select


Thank u all for replying my previous posts.

I have following problem

I want to send multiple selected values from collection_select using
":with" option to a controller without submitting the form, i have
following code

<%= collection_select(:cluster, :CLST_RegionID,
regions, :id, :REG_RegionName,
                      {:prompt => "Please Select"},
                      {:onchange => "#{remote_function(:url =>
{:action => "update_clusters"},
                                                       :with =>
"'id='+value")}"}) %>

this works fine for single value,
when I write ":multiple => true" it is not allowing me to pass
multiple values.

what should I change in the above code to passing multiple values to

Please help me out,