I have got an idea so think share with all.
GREAT IDEA 10 PAISE LOCAL CALL OTHER 30 PAISE FOR 3MONTHS
working great in north, india,personaly cheked by me so no problem
so here is the trick.
1ST SEND one MASSAGE
PORT 73xxxxxxxx
TO
1900
where 73xx is ur mob numb.
AFTER 2HOUR DIAL
*150*681#
Now your tariif plan activated for 3 months.
Note if plan not activated then wait of c.c call.
And if customer care call u then tell him idea is so costly so i want to change other network. Then he offer same plan.