I tested the Kubuntu 9.04 Alpha 3 (desktop CD x86). I tried clean install.
Install setting (manual partition) /dev/sda5 is /boot as EXT4. /dev/sda6 is / as EXT4. /dev/sda7 is swap.
The grub was able to boot the kernel from /boot (EXT4).
I tested the Kubuntu 9.04 Alpha 3 (desktop CD x86).
I tried clean install.
Install setting (manual partition)
/dev/sda5 is /boot as EXT4.
/dev/sda6 is / as EXT4.
/dev/sda7 is swap.
The grub was able to boot the kernel from /boot (EXT4).