Indeed, the LSI logic controllers that ship with some HP workstations do not provide adequate RAID protection and as such, is recommended that you either install another RAID controller in the machine or use software RAID.
Most onboard controllers are pretty lackluster, and those that use fake raid are obviously pretty hokey.
The LSI Logic MegaRAID 8888ELP is pretty good, although a bit pricey. I thoroughly dislike HP's own RAID controller offerings - had more problems with them than I care to mention here.
I hope you don't dislike HP's controllers designed for the its servers, like the P800 etc, as they are using the same chip as your preferred controller :) The e/p line of smart array controllers have been the most rock solid controllers (including my OE LSI's like the one you mention) I have ever used.
jlc