CMP problem - Error in the deployment fase

[freiburg]

I have this problem. When I make the deploy I have an error message as

"java.lang.StringIndexOutOfBoundsException: String index out of range: 0"

I think that the mistake is in the descriptor when I use the tag <method param> and put inside that java.lang.String.
But I don't know why. What do you think about?
Thank you very much for helping me!
Andrea

This is the local interface:

package com.sdb.stage.ejb;

import java.rmi.RemoteException;
import javax.ejb.EJBLocalObject;


public interface Cliente extends EJBLocalObject {

public Integer getCodice();

public void setCodice(Integer codice);

public String getNome();

public void setNome(String nome);

public String getPiva();

public void setPiva(String piva);

}


This is the LocalHome Interface

package com.sdb.stage.ejb;


import javax.ejb.EJBLocalHome;
import javax.ejb.CreateException;
import javax.ejb.FinderException;
import java.util.Collection;


public interface ClienteHome extends EJBLocalHome {

public Cliente create(Integer codice, String nome, String piva) throws CreateException;

public Cliente findByPrimaryKey(Integer codice)
throws FinderException;

public Collection findByName(String nome)
throws FinderException;

public Collection findByPiva(String piva)
throws FinderException;

public Collection findAll()
throws FinderException;

}


This is the Bean:

package com.sdb.stage.ejb;

import javax.ejb.EntityBean;
import javax.ejb.CreateException;
import javax.ejb.EntityContext;

public abstract class ClienteBean implements EntityBean {

private EntityContext context;

// Metodi di accesso per la persistenza

public abstract Integer getCodice();
public abstract void setCodice(Integer codice);

public abstract String getNome();
public abstract void setNome(String nome);

public abstract String getPiva();
public abstract void setPiva(String piva);


// Metodi specifici dell'entity bean

public Integer ejbCreate (Integer codice, String nome, String piva)
throws CreateException {

setCodice(codice);
setNome(nome);
setPiva(piva);
return null;
}

public void ejbPostCreate (Integer codice, String nome, String piva)
throws CreateException {}

// EJB callbacks
public void setEntityContext(EntityContext ctx) {
context = ctx;
}


public void unsetEntityContext() {
context = null;
}

public void ejbActivate() { }
public void ejbPassivate() { }
public void ejbLoad() { }
public void ejbStore() { }
public void ejbRemove() { }


}

This is the Deployment Descriptor

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE ejb-jar PUBLIC "-//Sun Microsystems, Inc.//DTD Enterprise JavaBeans 2.0//EN" "http://java.sun.com/dtd/ejb-jar_2_0.dtd">

<ejb-jar >

Cliente
<display-name>Generated by Freiburg</display-name>


<enterprise-beans>

<!-- Entity Beans -->



<display-name>Cliente entity bean</display-name>

<ejb-name>ClienteEJB</ejb-name>

<local-home>com.sdb.stage.ejb.ClienteHome</local-home>
com.sdb.stage.ejb.Cliente
<ejb-class>com.sdb.stage.ejb.ClienteBean</ejb-class>

<persistence-type>Container</persistence-type>
<prim-key-class>java.lang.Integer</prim-key-class>
False
<cmp-version>2.x</cmp-version>
<abstract-schema-name>cli</abstract-schema-name>
<cmp-field >
<field-name>codice</field-name>
</cmp-field>
<cmp-field >
<field-name>nome</field-name>
</cmp-field>
<cmp-field >
<field-name>piva</field-name>
</cmp-field>

<primkey-field>codice</primkey-field>


<query-method>
<method-name>findByName</method-name>
<method-params><method-param>java.lang.String</method-param></method-params>
</query-method>
<ejb-ql><![CDATA[
SELECT OBJECT(g)
FROM cli AS g
WHERE g.nome = ?1
]]></ejb-ql>



<query-method>
<method-name>findByPiva</method-name>
<method-params><method-param>java.lang.String</method-param></method-params>
</query-method>
<ejb-ql><![CDATA[
SELECT DISTINCT OBJECT(g)
FROM cli AS g
WHERE g.piva = ?1
]]></ejb-ql>



<query-method>
<method-name>findAll</method-name>
<method-params><method-param></method-param></method-params>
</query-method>
<ejb-ql><![CDATA[
SELECT OBJECT(g)
FROM ClienteEJB g
]]></ejb-ql>



</enterprise-beans>

<assembly-descriptor></assembly-descriptor>
</ejb-jar>