Alphora had a booth at Borland's conference a few weeks ago and I got to see a demo of their product. It was impressive and I wish I had had more time to look at it (at least I got one of their free t-shirts).
The product is written in C#. If Ximian can get a Linux C# compiler working, maybe you'll get to see Dataphor running in the *nix environment soon. Dataphor is extendable by any language that conforms to the specifications for Microsoft's Common Language Runtime (of which Perl and about another dozen languages comply).
Actually, I believe there is a FreeBSD implementation also. I just don't know how well these implementations work. Somehow, I distrust the concept of running something non-native on Unix. It should work, but I will have to be convinced that it will be stable, and perform up to par with native C/C++ applications.
But, I will be doing everything I can to figure this out.