Notice period

I am working with my current employer from last 2 years and now I have decided to join in another firm. The ideal notice period is 3 months or salary in lieu of thereof has been given but I can't serve complete notice period and I have informed my HR that I am agree to pay notice pay in lieu of 50 days notice as I will be serving for rest 40 days but she told me that this decision in entirely in my managers hand. I have seen incidents in my company where in an employee was relieved in 5 days. But in my case they are forcing me to stay for than i intend. Would like to ask the following:- 1) Is there any legal action that could be initiated against me, if I don't serve the 3 month notice period and only serve a 40 days notice period and pay a month's basic salary in lieu of remaining period? 2) what should i do even after i am intended to pay in lieu of salary but comany is forcing me to complete my full quota of notice period? Any Help in this tough would be appreciated... Thanks Rahul Any Help in this tough would be appreciated...