How use commandAPI?

Hi,

I want use commandAPI, but I have an Exception:

ERROR [com.mdm.testUtils.AbstractBonitaITCase] org.ow2.bonita.facade.exception.BonitaInternalException: Unexpected Exception arrived in Bonita: com.mdm.bonita.command.CommandSearchProcessInstance cannot be cast to org.ow2.bonita.util.Command

I have a class extends Command:

package com.mdm.bonita.command;

import org.hibernate.Query;
import org.hibernate.Session;
import org.ow2.bonita.env.Environment;
import org.ow2.bonita.persistence.db.HibernateDbSession;
import org.ow2.bonita.util.Command;

public class CommandSearchProcessInstance implements Command {

/** Generated uuid*/
private static final long serialVersionUID = 3148260409538618806L;

/** my variables */
private String v;

/**
* Constructeur
* @param variable
*/
public CommandSearchProcessInstance(String variable) {
this.v = variable;
}

public String execute(Environment env) throws Exception {
// Get the hibernate session
Session session = env.get(HibernateDbSession.class).getSession();
// use hibernate syntax to write your queries.....
Query query = session.createQuery("SELECT COUNT(instance) FROM org.ow2.bonita.facade.runtime.impl.InternalProcessInstance");

return query.uniqueResult().toString();
}
}

And after a Bonita Connexion I use this class like this:

AccessorUtil.getCommandAPI().execute(new CommandSearchProcessInstance(""));

I deployed my class CommandSearchProcessInstance.java in a file jar in my Tomcat classpath.

Please help me...