How can i put subs in allready authored dvd and keep menus?

[THE SERB]

How can i put subtitles in allready authored dvd and keep all the motions menu and everything?
Example i have SW:Empire strikes back and i want to take out german subtitles and put insted of them serbian subtiles!
I know how to rip movie with 5.1 sound import to dvd maestro put subtitle and make a dvd with english and serbian subtitles but with no motions menu and etc.
I know that there is something to do with ifo edit but i dont know how.I tried to find on google and yahoo but i cant find it!
Pls can anyone point me to the right direction with some link for some good tutorial or write down here som short tutorial.
Thx!

[Baldrick]

read https://www.videohelp.com/guides.php?guideid=598&howtoselect=6;34#598

remember to read the entire topic...lots of problems.

and please post dvd to dvdr in the dvd to dvdr forum. it includes adding new subs to commercial dvd.