ChEMBL

What options are there for a MySQL Chemical Structure Cartridge ? - the constraints are that the license needs to be Open (to commercial and non-commercial users). Post away in the comments, then everyone can see the answers.

Update: for a little background on our specific interests - we wish to build a deployable and distributable version (a package or vm) with a preconfigured and loaded current ChEMBL database, capable of performing full chemical search capability. Deployment could be as a Linux style package, or as an Amazon EC2 instance. Our internal systems here at the EBI are based on Oracle, and the MDL (or whatever the current name is :) ) Direct cartridge - this configuration is sometimes beyond the reach of many budgets, and so we are interested in exploring a 'free' but useful version of ChEMBL.

Update 2: So Postgres opens up quite a few more options....