安装gentoo后windows启动不了的问题

在安装windows时留下了30多G的空间用于安装gentoo，可是gentoo安装好后，发现进不了windows了，使用fdisk -l /dev/sda显示：
Disk /dev/sda: 250.1 GB, 250059350016 bytes
240 heads, 63 sectors/track, 32301 cylinders, total 488397168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xf980511a

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *          63    62914319    31457128+   7  HPFS/NTFS
/dev/sda2        62914320   488375999   212730840    f  W95 Ext'd (LBA)
/dev/sda3       488376000   488391119        7560   83  Linux
/dev/sda5        62914383   125828639    31457128+   7  HPFS/NTFS
/dev/sda6       125828703   230685839    52428568+   7  HPFS/NTFS
/dev/sda7       230685903   419428799    94371448+   7  HPFS/NTFS
/dev/sda8       419549823   423753119     2101648+  83  Linux
/dev/sda9       423753183   488375999    32311408+  83  Linux

我的/boot/grub/menu.lst文件内容如下：
default 0
timeout 3
#splashimage=(hd0,0)/boot/grub/splash.xpm.gz

title Windows XP
root (hd0,0)

title Gentoo Linux 2.6.36-r8
root (hd0,2)
kernel /boot/2.6.36-gentoo-r8 root=/dev/sda9

不知道是什么原因，求高手们指点，谢谢！

Answer:
title windows xp
        rootnoverify (hd0,0)
        chainloader +1