Firstly, we need to establish whether or not you're missing mortgage repayments because you don't have the money, or simply because you refuse to pay. If you simply don't have the money, then you should approach the lender and discuss your options. If they are not satisfied with your capacity to repay, then it's likely they will take you the court. If this happens, the best thing you can do is to comply with whatever the judge orders. Once you're doing everything you can, it's highly unlikely that a judge will put you in jail.
It was only reported today that 276 people have faced jail time last year because they were unable to pay their debts. If you ignore them problem, you will become another statistic.