I've just done this, and encountered a few problems and gotya's so here goes.

1) upgrade the firmware so the Smart Array can be found

2) - use the kernel raid.s - This means you can see the devices
3) - the Devices appear as :-
/dev/cciss/c0d0 [internal Drives]
/dev/cciss/c1d[1-9] [external Smart Array Drives - depends how you've configured it at boot up]
4) - during setup when installing lilo this will fail, [or may pass but still not work] - you will have to do the chroot trick and edit the lilo.conf file so that the boot line says :-
boot = /dev/cciss/c0d0
and not
boot = /dev/cciss/c0d0p1 [or whatever]

I'm not sure why this happens, it just confused me for a bit.

5) copy the correct config file from the CD into the kernel source and run your favorite config options [make config, menuconfig, etc...] and select SMP [CONFIG_SMP=y] and Large Memory 4GB [CONFIG_HIGHMEM=y]
rebuild everything [make dep; make modules; make modules_install; make install ]

6) add
alias eth0 tg3
to /etc/modules.conf, I'm not sure why this failed to get installed automagically - I'm pretty sure it did the 1st time though but not when I did the final install]

7) reboot

8) wait for it to come back up - 2TB partitions do take a while to initialise

Thats it for the moment but I may add to this as I come up with other stuff [I'm filling one of the large partitions now over the network - takes a while], then I going to do some tests on speed of the arrays

It all works fine...
I was waiting on Slackware 11 to make it go live however I'll migrate everybody across to the new one and then do a Slack 11 install on the old machine.