Well, as the listing says, it's SPP, not HID, so kbdd is exactly what you need to use it. Fanoush has kbdd here, with some instructions. (There's no version labeled for N810, so just use the N800 version.) For getting root access, see the wiki here.

(Or buy a regular HID keyboard and try to sell this one, but this stuff's not that hard once you get into it...)