First of all, you got only little knowledge on that and Little knowledge is very dangerous.

Any passports issued on or after April 1, 2010 must be Machine Readable Passports (MRPs).

All passports issued before April 1, 2010 should be replaced by MRPs by the year 2014. So don't worry dude. Well regarding how u replace ur passport, u need to send to nepalese embassy on country u live for replacement. But u need to wait may be a year because no way it would be available within a year in our embassy.

Also, no way that nepal can start issuing MRPs from april 1, 2010. well Nepal has requested for temporary extension of deadline of issuing MRPs  to the concerned international authority. Only if they reject to extend deadline, nepalese people getting passport after april 1, 2010 are in problem.

You or any nepalese currently having passport are fine.