I am using CM10 with Semaphore JB
You will need fixrecovery.tar and Odin (I used v1.83) you can download them in attachments.
For those who don't have flashable kernel on Internal SDCard can skip step 5 and second half of step 3.
1. So first of all you have to remove SIM and SDCard.
2. Flash fixrecovery.tar with Odin and uncheck Auto Reboot
3. Get into recovery and wipe only cache and flash kernel you want
4. Flash normal kernel with Odin and again uncheck Auto Reboot
5. Get into recovery and again flash kernel of your choice
6. Now you should be ready to switch your phone on
Maybe this excessive flashing of kernel is not necessary but I did it this way