yes i have implemented it but it is not working for numerics .numerics are also getting sorted in the same way as that of strings.
i.e for example if i have values like 2,4,6,8,10,11,12,13,14,20,21....
when i click on column header it is sorting in this way.
10,11,12,13,14,2,20,21...which is exactly the string sort...
but i want it to get sorted in the numerics way...i.e 2,10,11,12,13,14,20,21....

can u plz help me...i am in great need of it.

thank u
vinnu