Unable to start-database in Ubuntu Linux

The readme file says that under Linux I need to start the database. But it won't start. I don't see mention of start-database in the or-install-guide-3.0.pdf, although there is mention of NoClassDefFound (but it is not obvious whether jar for hsqldb would be sensitive to lack of X, particularly as I haven't tried invoking tomcat nor catalina). I suspect there is a bug in the documentation, rather than the software.

$ bash database/start-database.sh

command not foundbase.sh: line 6:
Exception in thread "main" java.lang.NoClassDefFoundError: org.hsqldb.Server
at gnu.java.lang.MainThread.run(libgcj.so.81)
Caused by: java.lang.ClassNotFoundException: org.hsqldb.Server not found in gnu.gcj.runtime.SystemClassLoader{urls=[], parent=gnu.gcj.runtime.ExtensionClassLoader{urls=[], parent=null}}
at java.net.URLClassLoader.findClass(libgcj.so.81)
at java.lang.ClassLoader.loadClass(libgcj.so.81)
at java.lang.ClassLoader.loadClass(libgcj.so.81)
at gnu.java.lang.MainThread.run(libgcj.so.81)
$