Can't boot after upgrade to FC6

[zephod at cfl.rr.com]

The upgrade from FC5 to FC6 appeared to go OK at first and I was able 
to log in and do a package update which had no problems. However after 
I installed xen I can no longer boot; the system just reboots.

After some investigation I found that when I boot from the DVD in 
rescue mode and run grub from the command line I get this:

# grub
grub> root (hd0,0)
   Filesystem type unknown, partition type 0x7

The file /boot/device.map contains:
 (hd0) /dev/hdi
 (hd1) /dev/sda

hd1 is my Windows disk.

Parted shows me this:

# parted /dev/hdi

Model WDC WD1600JB-00FUA0 (ide)
Sector size (logical/physical): 512B/512B
Partition table: msdos

Number Start  End   Size  Type    File system Flags
 1     32.3KB 107MB 107MB Primary ext3        boot
 2     107MB  160GB 160GB Primary             lvm

I noticed from reading the grub manual 
(http:\\www.gnu.org\software\grub\manual.htm#Features) that it does 
not list ext3 as one of the supported filesystem types. 

Is this my problem or is the manual not up-to-date? If this is the 
problem how do I change the boot partition from ext3 to ext2 and how 
did my FC5 system boot? 

The other thing that looks odd to me is that the partition table is 
msdos. Is this correct?

Answers to these questions or any other suggestions will be 
appreciated.

Thanks,
Steve