I have an Adaptec 6405 ... according to Adaptec documentation, LVM partitioning isn't supported with the 6 series cards under Debian.
Absolutely it works under debian. We had it running there with LVM, just not Proxmox. After bribing, they have kindly added support for it in the latest ISO. We are setting up a box with one now, and so far install is going smoothly. Will post results sometime tomorrow when the raid 10 is finished building.