Ubuntu Netbook Remix / Ubiquity / No paritions listed

Trying to install UNR from a USB stick (tried both direct install from the boot menu and from ubiquity icon on the 'live' version) and so far no joy.

Laptop is an MSI U100 with a 200GB SATA drive with the following partition scheme
sda1, ntfs, windows 7, boot, 100GB
sda5, extended partition
sda6, linux swap, 4GB
sda7, linux ext4, 10GB
sda8, linux ext4, <rest of disk>

gparted / fdisk on /dev/sda show the partition tables fine and let me change them happily.

Sadly on the select/configure partitions screen Ubiquitiy isn't showing /dev/sda and won't let me specify a device to install to.

I've happily in the live CD mode mounted the two ext4 partitions and written to them fine so /dev/sda is working fine under Linux and windows, just doesn't seem to like ubiquity :-(