smp kernel 760 boot failure, can't read superblock

[Anne & Lynn Wheeler]

i've got a pair of sata drives .... logical volume boot filesystem that 
is marrowed on the two drives and all the other file systems are 
striped. smp kernel 681 boots fine, the three subsequent kernels that 
i've tried (including 760) all fail in boot with error message about not 
readying superblock