Dual boot with galaxy s3

Hello i think is the good point for make this post!


sorry for my english
i got samsung galaxy s3 with rom Supernexus 4.1.2 and kernel siyah 1.7cr1
mi recovery is siyah 6.0.1.4
i try to dual boot
I copy my first rom in the second

but when i try to make:
Wipe data/chace 2nd rom o install to 2nd rom gve me
"not implemented yet" how i can resolve??
only copy and remove work, i don't know why...


ps. and if I backup my prefer and first rom, install AOPK jb, copy 1s to 2nd rom ( the only dual boot option work) and after i make wipe data del and restore my first rom? is ok you think?
many thanks!