Sebastian ported an early version of the ACS (1.3) to InterBase 4.0/Linux. Though I'm not 100% positive, I believe it was before he became employed by aD (which, I'm sure only helped him get a job). His ACS 1.3 port has not been maintained through ACS 2.x & 3.x. (Porting a 1.x version of the ACS would be lots simpler than 2.x or 3.x. In fact, had Solid at that time supported triggers & sequences directly in inserts, I would have attempted a 1.x port to Solid myself.)
Now that InterBase 6.0 has been open sourced, I imagine he's (personally) interested in ACS/InterBase again. Now, as to why aD (as opposed to Sebastian personally) would want to do an InterBase port.....? I don't understand why they'd suddenly want to be in the porting business (after having the all-mighty Oracle outlook-on-life, they've had) and when OpenACS is already working on porting to open-source databases. (It would seem more effective, and also a better PR move, for aD to allow Sebastian to spend time working as an OpenACS volunteer.) Who knows.
