Maintainance

Respected Experts, Details: My wife got maintainance of 12 thousand rupees every month and hon'ble megistated ordered to pay the amount from the date she filed the case (march 2010). As i am out of country I haven't attended in the court and not contsted on the same. She is very well educted (M tech) and came from a settelled family. And also she is working as professor where she is earning almost 30 thousand rupees every month. We came to know her working status rescently. I just wan to intimate that I have not taken single penny either from her or parents as I am against dowry. I have few questions: 1. As the total amount is crossing 8 lak rupees and I am not in a very good job, I can't pay the amount. So can i initially pay 50 thousand to 1lak? 2.The case filed and orders (judgement) came in District court, can I file petition by requesting to change the payment to start from the date of order, instead of date of case file. if so which court i have to approach (District/ High court). 3. As she is earning a very good amount and she has a very good family back ground, can i request to reduce the maintainance amount? If so where I have to file the case (district court or high court)? I heartful regards in advance for your help. Venkat P