Clistview Sorter With Multiple Conditions....

Dear all,

I have a CListView Sorters like the following;

'sortableAttributes'=>array(
        'create_time'=>'Post Time',
        'money'=>'Money'
    ), 

This CListview is a list of transactions. In the transactions table, there is a column called "closed". When closed is set to 1, means the transaction is closed and I ALWAYS want the closed questions appear at the bottom of the list.

Right now, when you click sort by money, the smallest/biggest amount of money transaction will show up, even it's closed. What I want is it sorted by "closed ASC, money DESC" or "closed ASC, money ASC" when you click the sorter "money" Is there a way to implement these multiple conditions to the sorter?

I tried to set the sort in my data provider but still does not work!

                'sort'=>array(
                    'attributes'=>array(
                         'money'=>array(
                              'asc'=>'closed ASC, money ASC',
                              'desc'=>'closed ASC, money DESC',
                          ),
                     ),
                 ),

Thanks so much for your help!!!