I've noticed many different configurations for Weblogic.  I've read through much of the e-docs for Weblogic and here is a configuration that is minimal and effective for CMT, JNDI bound session factory,...
Code:
<hibernate-configuration>
  <!-- a SessionFactory instance listed as /jndi/name -->
  <session-factory name="hibernate.HibernateFactory">
    <!-- Bind the SesssionFactory to JNDI -->
    <!-- JNDI DataSource Connection -->
    <property name="connection.datasource">hibernate.DataSource</property>
    <!-- Transaction Management Properties-->
    <property name="transaction.manager_lookup_class">
      net.sf.hibernate.transaction.WeblogicTransactionManagerLookup
    </property>
    <property name="transaction.factory_class">
      net.sf.hibernate.transaction.JTATransactionFactory
    </property>
    
    <!-- Miscellaneous Properties -->
    <property name="dialect">net.sf.hibernate.dialect.MySQLDialect</property>
    <property name="show_sql">true</property>
    <property name="use_outer_join">true</property>
    
    <!-- mapping files -->
    <mapping resource="..."/>
    
  </session-factory>
</hibernate-configuration>
Surely, if someone sees something that can be improved please mention...
Thanks
Joe W