Actually, it is the exact same method that I'm using.
The only thing is I gave you a wrong link
Here was the good one :http://androidblogger.blogspot.com/2009/05/how-to-ship-application-with-pre-baked.html
So, as in this other blog, I copy the database from the .apk to the database dir.
I can't even claim this guy copied me, he posted it before !!
As a side note : there is a sensitive comment that said that it could be a good idea not to embed the database in the .apk, but to dowload it as a first installation step, to avoid to have the database twice on your phone !