Sorting on Two columns in Webi 4.0

My requirement is:-

I am working on Webi 4.0.I have a report with a cross-tab and break and sorting is applied on the first column.There are two more columns on which I want to apply sort as follows:-

1   2   3

X   4   A

Y   5   B

Z   2   C.

I want to see the values as:-

1 2 3

X 5 A

Y 4 B

Z 2 C.

I have a requirement that in the third column the row with value "A" should always be displayed first and the highest value in the second column should be displayed first.If I apply ascending sort on column 3 then 2 column is not sorted from highest to lowest.The same applies to column 3.I tried setting the priority of the sort but it doesn't meet my requirement.

I hope I have made myself clear.

Any help on this would be appreciated.