did you read and understand the install instructions?
"root (hd0,0)"
hd0,0 is the FIRST partition on the FIRST drive
you already stated you put grub on the 6th partition of the first drive ( sda5 )
that should read
I am guessing that suse12 is on
sda1,sda2,sda3,and sda4 ( well sad4 will be an extended partition )
what are you using to boot both?
suse grub on sda1 to boot both
or
suse boot on sda1 to chainload to sha5