Don't know where to look anymore.
I have a Session Bean with the following ejb-jar.xml:

<?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 >

 <description><![CDATA[No Description.]]></description>
 <display-name>Generated by XDoclet</display-name>

 <enterprise-beans>

 <!-- Session Beans -->
 <session >
 <description><![CDATA[EJB Test]]></description>

 <ejb-name>MpBean</ejb-name>

 <home>pt.ejb.MpHome</home>
 <remote>pt.ejb.Mp</remote>
 <local-home>pt.ejb.MpLocalHome</local-home>
 <local>pt.ejb.MpLocal</local>
 <ejb-class>pt.ejb.MpBean</ejb-class>
 <session-type>Stateless</session-type>
 <transaction-type>Container</transaction-type>

 </session>

 <!-- Entity Beans -->

 <!-- Message Driven Beans -->

 </enterprise-beans>

 <!-- Relationships -->

 <!-- Assembly Descriptor -->
 <assembly-descriptor >

 <!-- finder permissions -->

 <!-- transactions -->
 <container-transaction >
 <method >
 <ejb-name>MpBean</ejb-name>
 <method-name>*</method-name>
 </method>
 <trans-attribute>Required</trans-attribute>
 </container-transaction>

 <!-- finder transactions -->
 </assembly-descriptor>

</ejb-jar>

My objective is to use CMT.
The SB gets deployed successfully and when I execute a SB method it gives no error.
But no changes are made to the DB! That's my problem. Looks to me that no "commit" is being done.
Is there another file that I need to configure besides ejb-jar.xml to enable CMT?

Really need help on this. Giving me headaches.