The tool supports Oracle, IBM DB2, MS SQL Server and Sybase. The tool is written in Java and employs a framework approach so adding new checks is done via an upgrade rather than a re-install.
I tested the tool locally against an Oracle database and got some results. There is a lot of Oracle checks, in excess of 100, some of which are old and I felt incorrect - in terms of results and also levels of severity. Also I was not enamoured by the registration process which failed for me! I sent some feedback to Imperva and they will take it on board, they have let me know that they will start a forum to allow feedback to be given more easily.
The tool is free though and its a good tool that wll get better with feedback and development. Get on over to Imperva and download it, its worth a look.