Hibernate – Using Hibernate with SQL Server 2008

I'm using SQL Server 2008 with Hibernate 3.0 at data access layer of my application. The problem is that I'm unable to read from database.
Here is my Hibernate config;

<property name="connection.driver_class"> com.microsoft.sqlserver.jdbc.SQLServerDriver</property>
<property name="connection.url">jdbc:sqlserver://localhost;databaseName=test;integratedSecurity=true;</property>
<property name="connection.username">not required</property>
<property name="connection.password"></property>
<property name="dialect">org.hibernate.dialect.SQLServer2008Dialect</property    
<property name="hibernate.hbm2ddl.auto">update</property>    
<mapping resource="user.hbm.xml"/>

Here is user.hbm.xml

<class name="ammar.User" table="user" schema="dbo" catalog="test">
    <id name="userId" type="int" column="userId" >
        <generator class="assigned"/>
    </id>

    <property name="userName">
        <column name="userName" />
    </property>
</class>

And here is code I'm using to get data from database.

    SessionFactory sF = new Configuration().configure().buildSessionFactory();
    Session session = sF.openSession();

    User user = (User) session.get(User.class, 1);

    if(user!=null)
        System.out.println(user.getUserName());
    else
        System.out.println("Not Found");

SQLGrammarException as well as SQLServerException occurs when I run this.
Urgent reply is needed.