In the near future we will have support for using Firebird Relational Database.
Thanks to Gareth Goslett from South Africa who is the developer/maintainer of this new Data Layer.
We will first have this in the 1.x version of mojoPortal for 1.1 .NET/Mono and will follow up after that with a version for 2.x mojoPortal
Initial code has already landed in svn/trunk
Lots of other good things happening with mojoPortal that I will blog about soon.