error on installation ubuntu(grub, ubiquity., etc)

Sorry for Japanese
ubuntu 12.04 wo install tyuu ni grub no error ga hassei shimasita.
hardware toshite SSD 6Gbps wo tukai mashita.
install OS ha ubuntu 12.04 64 bit desu.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: ubiquity 2.9.23
ProcVersionSignature: Ubuntu 3.2.0-17.27-generic 3.2.6
Uname: Linux 3.2.0-17-generic x86_64
ApportVersion: 1.93-0ubuntu2
Architecture: amd64
CasperVersion: 1.305
Date: Wed Mar 21 20:10:54 2012
InstallCmdLine: file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd.lz quiet splash -- debian-installer/language=ja keyboard-configuration/layoutcode?=jp keyboard-configuration/modelcode?=jp106
LiveMediaBuild: Ubuntu 12.04 LTS "Precise Pangolin" - Beta amd64 (20120301)
ProcEnviron:
 LANGUAGE=ja_JP.UTF-8
 TERM=unknown
 PATH=(custom, no user)
 LANG=ja_JP.UTF-8
 SHELL=/bin/bash
SourcePackage: grub-installer
UpgradeStatus: No upgrade log present (probably fresh install)