Problem with stripe across mirrors

[Jason Hitt]

I'm running into a big problem with a new 4 disk array im attempting to 
configure.

I'm using an SIIG 3114 PCI SATA controller with four WD3200SD 320 gig 
disks attached to it.  This is only going to be bulk storage, not a 
system disk.  The disks appear in the system as ad{4,6,8,10}.  My test 
is to configure my geom provider and then dump/restore a 100 gig mount 
from a separate provider.

Setup:

apply "dd if=/dev/zero of=/dev/%1 bs=512 count=79" ad4 ad6 ad8 ad10
apply "fdisk -v -B -I /dev/%1" ad4 ad6 ad8 ad10
I then go back in with "fdisk -v -f- -i /dev/ad?" and reduce the size of 
the slices by 1 so the consumers will be ad?s1, not ad?.

 From this point i can successully use gmirror to mirror 2 disks and run 
my test, or i can use gstripe to stripe 2 disks and run my test 
(presumably a stripe across all 4 would work as well, but this is 
untested).  The failure comes when i do this:
gmirror label storage0 ad4s1 ad6s1
gmirror label storage1 ad8s1 ad10s1
gstripe label storage mirror/storage0 mirror/storage1
newfs /dev/stripe/storage

At this point i mount /dev/stripe/storage and attempt to copy data to it 
using dump/restore (a large cp suffices as well).  After a random amount 
of time (typically < 60 seconds), the system will completely hang.  
There is no panic, there is no crash.  The system is completely hung.  
With no crash dump or panic, it's quite difficult to pinpoint the 
problem.  I also cannot find any solid resources to use as a "how-to" 
for a geom raid10 setup, so i'm not sure if im approaching it correctlly 
or not.

Anyone familiar with this that can lend a hand?

Jason Hitt