Error while creating tool instance for barna.astalavista.AStalavista

Hello,

I have the following error, can you help me solve it ?

[scaon@erwan bin]$ ./astalavista --help
Astalavista v3.1 (Flux Library: 1.21)

[ERROR] Error while creating tool instance for barna.astalavista.AStalavista
java.lang.InstantiationException
at sun.reflect.InstantiationExceptionConstructorAccessorImpl.newInstance(InstantiationExceptionConstructorAccessorImpl.java:48)
at java.lang.reflect.Constructor.newInstance(Constructor.java:525)
at java.lang.Class.newInstance0(Class.java:374)
at java.lang.Class.newInstance(Class.java:327)
at barna.commons.launcher.Flux.findTools(Flux.java:410)
at barna.commons.launcher.Flux.main(Flux.java:104)
[ERROR] Make sure the class exists and has a default constructor.