"No root file system" during install.Unable to install Kubuntu 6.1 via installer

[PowerUser]

Using Kubuntu 6.1 x64 (official Edgy relese).
My system is AMD Athlon 64 x2 3800+ on MSI K9N Platinum motherboard (nForce 570 chip set), 1 Gb DDR II (dual-channel) RAM, 2 x DVD RW, ATI x1300 graphic card and 3 HDDs.

About HDDs:
First (sda) has 4 partitions:FAT32, NTFS, EXT2 (with Kubuntu 6.06.1 installed), remainder is big EXT2 (for data storage).I'd tried to install Edgy on this HDD over Kubuntu 6.06.1 and after manual partitioning (I'm not willing to trash my data, really) installer always stucks with "No root file system" error.However 6.06.1 installs OK in same configuration.

Then I bought 2 another HDDs.Today I'd tried to install Kubuntu 6.1 onto clean HDD (sdb).

Partitioner had some unfair issues with manual partitioning.It failed to create EXT3 or NTFS partitions.Only EXT2 and Fat32 worked for me so HDD now contains FAT32 partition, then unformatted one(intended to be NTFS but formatting fails), then EXT2 (intended to be /) and another EXT2(intendeed to be data store).So, finally partitions were here.I'd selected partitions in installer for / and other mount points but ... installer refused to install again with "No root file system".This actually prevents me from installing KUbuntu 6.1 since I'm not a Linux guru (at least now).

[PowerUser (i-am-sergey)]

Partitions info:

Disk /dev/sda: 203.9 GB, 203928109056 bytes
255 heads, 63 sectors/track, 24792 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot Start End Blocks Id System
/dev/sda1 * 1 1958 15727603+ c W95 FAT32 (LBA)
/dev/sda2 1959 4569 20972857+ 7 HPFS/NTFS
/dev/sda3 4570 8094 28314562+ 83 Linux
/dev/sda4 8095 24792 134126685 7 HPFS/NTFS

Disk /dev/sdb: 320.0 GB, 320072933376 bytes
255 heads, 63 sectors/track, 38913 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot Start End Blocks Id System
/dev/sdb1 1 2611 20972826 b W95 FAT32
/dev/sdb2 * 2612 5875 26218080 83 Linux
/dev/sdb3 5876 8486 20972857+ 7 HPFS/NTFS
/dev/sdb4 8487 38913 244404877+ 83 Linux

Disk /dev/sdc: 320.0 GB, 320072933376 bytes
255 heads, 63 sectors/track, 38913 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot Start End Blocks Id System
root@sk-sys:/media/e#

[PowerUser (i-am-sergey)]

Found bug #67130 which seems to be same :(
Probably bug should be closed...

[Yves Meunier (yves.meunier)]

Same problem with ubuntu 6.10. Ihave choosen these disk

/ -> /hdc1, format
/home -> /dc3, do not format
swap -> /hdc2, format
/mount/FAT32 -> hdc4, do not format