When using the global config API factory methods, OSGi class loading configuration fails:

db = service.openFile(fileName);
=>
java.lang.ClassCastException: com.db4o.reflect.generic.GenericObject

Workaround until fixed: Pass an explicit config argument (recommended, anyway).

Configuration config = Db4o.newConfiguration();
// ...
service.openFile(config, fileName);

Reported in forums: http://developer.db4o.com/forums/thread/46690.aspx