Sort columns after another column(date '2012.01.01'/number 'new[1212]')

greeed

Hi,

I have a table:
___date__ name____number______info_info2_number2
2012.01.18 ažžž new[153112122j2] xxx zzzz cc[1231]
2012.01.18 ąąčč newer[asd234636] yyy kkkk cc[2131]
... .... ..... .... ... ...
So what i want to do is click on date(aromatically sorts the column) and THEN click+shift on name column to sort that column by the date column. Or sort the number column, and THEN click+shift on date/name... So basically this code allows me to sort the table on any column,
but when I try to sort multiple columns using click+shift I'm unable to do so when the first column is date (2012.01.18) or number(new[1531])
or number2

the code:
[code]
$('#aaa').dataTable(

{
"bPaginate": false,
"bLengthChange": true,
"bFilter": true,
"bSort": true,
"bInfo": false,
"bAutoWidth": false,
"aoColumns": [
null,
null,
null,
null,
null,
null
]

});[/code]
maybe I have to change the date column type from null to ??? and change the type of number&number2?
everything else works... except dorting second column after the first, when the first is date/number/number2