duplicating extras to both the split dvds

[dvdthirsty]

Hi,
I have a double layered dvd with a movie in it. It has got 4 audio languages. The movie is structured in the following way:
SIZE | FILE_NAME
--------------|---------------
12,288| VIDEO_TS.BUP
12,288| VIDEO_TS.IFO
14,483,456| VIDEO_TS.VOB
161,792| VTS_01_0.BUP
161,792| VTS_01_0.IFO
21,403,648| VTS_01_0.VOB
1,073,676,288| VTS_01_1.VOB
1,073,676,288| VTS_01_2.VOB
1,073,676,288| VTS_01_3.VOB
1,073,676,288| VTS_01_4.VOB
1,073,676,288| VTS_01_5.VOB
1,073,676,288| VTS_01_6.VOB


The VTS_01_0.VOB file has the main menu(Play movie, Chapters, Songs).
There is another menu(actually an extra) which is in the begening of the VTS_01_1.VOB file. This menu allows to select between the 4 audio languages.
Now I want to back up this DVD. So i have to split it into 2. After splliting, the first DVD allows me to select between the audio languages. But the 2nd DVD does not have the menu for me to select the audio languages even though it has the main menu(Play movie, Chapters, Songs).
Can anyone help me to add the audio language menu to the 2nd dvd?

Thanks