Found simple way to root JVU and keep it near to stock.
Download Easy Rooting Toolkit
Follow the instruction on the command prompt or screen above.
1. Enable "USB DEBUGGING". Menu>Settings>Applications>Development
Note: Make sure you have installed ADB drivers for your device (it inside Andorid SDK or KIES)
2. After enabling "USB DEBUGGING" connect phone to pc and let it download and install all the drivers
3. Enable "UNKNOWN SOURCES". Menu>Settings>Applications
Note: [OPTIONAL] increase screen timeout to 10 minutes
4. Connect USB cable to PHONE and PC
5. Run "runme.bat". DONE
Your phone will be rooted and superuser installed :)
Thank to $omator. Continue reading here