Erro ao conectar com websphere

Galera bom dia, poderiam me ajudar com esse problema, já estou quebrando a cabeça.
valeu obrigado!

error

04/10/2013 20:38:36 null null WARNING: WSVR0072W 04/10/2013 20:38:37 null null WARNING: WSVR0072W 04/10/2013 20:38:37 null null WARNING: WSVR0072W 04/10/2013 20:38:37 null null WARNING: WSVR0072W 04/10/2013 20:38:37 null null INFO: Client code attempting to load security configuration Exception in thread "P=915506:O=0:CT" java.lang.Exception: Falha na conexão com o SISE: Exception occurred while the JNDI NamingManager was processing a javax.naming.Reference object. at br.com.sise.model.conexao.Conexao.getDS(Conexao.java:50) at br.com.sise.model.conexao.Conexao.getConnection(Conexao.java:92) at br.com.sise.controller.util.ConnectionFactory.getConnection(ConnectionFactory.java:26) at br.com.sise.controller.webservice.Teste.main(Teste.java:22)

codigo

[code]public class Conexao {

private PreparedStatement pstm;
private Connection conn;
private DataSource ds = null;
private boolean isConexaoInterna = true;
private static Conexao instance = null;

public Conexao(Connection conexao) 
{
	conn = conexao;
	isConexaoInterna = false;
}

public Conexao() {
	conn = null;
	isConexaoInterna = true;
}

protected void finalize() throws Exception {
	desconectar();
}

private DataSource getDS() throws Exception 
{
	if(ds==null)
	{
		synchronized(DataSource.class)
		{
			try 
			{
				Context initialContext = new InitialContext();
				ResourceBundle  properties = ResourceBundle.getBundle("br/com/projeto/model/conexao/config_database");
				String conexao_nome = properties.getString("conexao_nome");
				ds = (DataSource)initialContext.lookup(conexao_nome);
			}
			catch (Exception e)
			{
				throw new Exception("Falha na conexão com o banco: " +  e.getMessage());
			}
		}
	}
	return ds;
}

//Abrir a Conexão
public Connection getConexao() throws Exception {
	if (conn==null) conn = getDS().getConnection();
	return conn;
}
public void liberarStatement() throws Exception {
	if (this.pstm != null) {
		try {
			this.pstm.close();
		} catch (SQLException sQLException) {
		}
		this.pstm = null;
	}
}

//Fechar Conexão
public void desconectar() throws Exception {
	liberarStatement();
	if (isConexaoInterna && this.conn!=null) {
		try {
			this.conn.close();
		} catch (SQLException sQLException) {
		}
		this.conn = null;
	}
}

public static synchronized Conexao getInstance() {
	if (instance == null) {
		instance = new Conexao();
	}
	return instance;
}

public Connection getConnection() throws Exception {
	return getDS().getConnection();
}

}

[/code]