Conversion To a Java Database

Has any though been given to convert the database to a Java based one and then the application could be written for cross-platform compatibility. I currently use Linux almost exclusively, and to be able to use RELMA, I load a Windows XP virtual machine in VMware. It would be very convenient to be able to use the RELMA application in Linux. It is possible to import the data into HSQLDB ( but I was wondering about the possible copyright issues.

Would it be sufficient to convert to a cross-platform database that is Java-accessible, like SQLite or Berkeley DB?