It's fairly well known and a reasonable implementation. It was/is good enough for Oracle to adopt it as the J2EE engine for their latest database offerings. Have you got any specific questions about Orion ?
We are using Orion for our production environment and it works great (fast, reliable, and easy to maintain). From what I understand, it is the closest to implementing the J2EE standard. Best Regards, Matt [This message has been edited by Matt Midcap (edited July 09, 2001).]