If you want to build the latest and greatest of KDE 4.0.72 you will need to have Akonadi 0.80.0 built first as things seems to break without this package. Let me save you a lot of time by giving you an Akonadi package. It took a while for me to realize that there was a snapshot (here) of Akonadi available on the KDE mirrors in one of the support directory. I’ve basically took soprano built script from Robby Workman and modified it for Akonadi.
You can get Akonadi package here.
And the Akonadi Slackbuild script here.
Enjoy.