It's indeed clear that the databases are not physically compatible, but it'd be just enough if you and Cepi would be so kind and provide their format to us. I understand that the bear-hunters (btw, Whatsup is developed by that football player, right?) don't wanna make public your whatsapp protocol hacks, but why such a thing as the database format can be made public so that they use their time on more important things and let the others to write database converters, no?

PS: 5 years ago, I'd take your "only Cepi / only me" as a challange ;-)
EDIT: actually, just briefly looked at it and isn't it that both Cepi and you are using SQLite? So it's just enough to match the corresponding columns and write a small conversion script.