Actually, you'll need to create a file, for example:
/etc/modprobe.d/aic7xxx
And put this in it:
options aic7xxx max_luns=128
** Changed in: linux-meta (Ubuntu)
Sourcepackagename: linux-meta => linux-source-2.6.15
Status: Unconfirmed => Rejected
--
Kernel does not detect all luns.
https://launchpad.net/bugs/52260