help:EJB lookup error

[fans]

hi everyone:
i received the error message below:
javax.naming.CommunicationException: Receive timed out [Root exception is java.net.SocketTimeoutException: Receive timed out]
when i lookup EJB.
i am testing the InterestClient examples of jboss examples.
The example is almost not changed at all.The enviroment of my server is:jboss3.0.0-beta ,jdk1.4.0.
the jndi name of EJB if interest/Interest, EJB-name is Interest.
properties.put("java.naming.factory.initial","org.jnp.interfaces.NamingContextFactory");
properties.put("java.naming.provider.url","jnp://localhost:1099");
properties.put("java.naming.factory.url.pkgs","org.jboss.naming:org.jnp.interfaces");
Context ctx = new InitialContext(properties);
//look up jndi name
Object ref = ctx.lookup("interest/Interest");

[greenwaves]

properties.put("java.naming.provider.url","jnp://localhost:1099");

--> properties.put("java.naming.provider.url","localhost:1099");

[greenwaves]

properties.put("java.naming.provider.url","jnp://localhost:1099");

-->properties.put("java.naming.provider.url","localhost:1099");