Rounding of in sales posting

Dear All,

There is requirement to round off in all sales posting.

All amount in paise to be rounded to next rupee if greater than 50 paise else round down to earlier rupee.

I tried by changing the rounding rule to A in the condition type but that didn't seem to solve my problem and not finding any Exit either for this. 

Can any one please guide me how to achieve this.

Best Regards -

AL