I have not had time to implement but, recommend trying with the Pro or Ultra series.
1. Setup VBox: Follow my guide post here for x86.
2. Install CentOS 6.2 or 6.3 as VM
3a. Follow "Quick HOWTO: Kolab 2.4 on CentOS 6.2"
3b. Follow "Quick HOWTO: Kolab 3.0 pre-alpha on CentOS 6.3"
Looks like OwnCloud will be integrated into Kolab 3.0 by final release.