Hi all!
I wanna thank you all, specially Fanoush and also n9mjg! This forum is great, since I got my N800 last month you solved all issues I got!
My Zaapa BK600 is now working. I found that it was the same as a Chainpus Smartphonemate BK600 / Freedom Keyboard so I chose "KBTYPE=freedom" and it is (finally!) working with my N800/OS2008.

I just have two minor issues:
- sometimes I have to press some key twice;
- AltGr key is not recognized, and so can't use some symbols;

I must admit haven't read Fanoush' documentation yet, so I will research/google better and if I find any solution I'll post it here.