3rd Fedora disk curdle

[Gerard J. Cerchio]

In the short time I have been working with olpc I have had my Fedora 
VMware machines curdle their ext3 disks 3 times.

I have been running 2.4 and 2.6 Redhats and Debians for over a year with 
no such problems. Once the first Fedora 7 machine broke its disk I have 
been very careful to shutdown every time. I cannot point to any 
particular activity that has corrupted the disk image. Things will start 
to go "wrong" and a subsequent reboot with fschk will yield a disk 
hopelessly in trouble.

Does the jhbuild emulator do any exotic direct to disk IO that may be 
causing this?
Does Fedora aggressively modify its ext3, vfs or SCSI drivers?

I have built a third Fedora 8 VM this time using IDE disk IO in hopes 
that this problem will go away.

Has anyone else seen this kind of problem?

-Gerard