Cannot instantiate EJB after configuring EJB security roles PLEASE HELP!!!

I just managed to properly configure my stateless session bean with respect to the security roles in the ejb-jar.xml and the ejb-j2ee-engine.xml file (see below). I also configured the security roles in the security provider service tab within the Visual Administrator (added a security role rmsadmin of type security role) and then added some user to this role.

The deployment went fine but when I started the application with the modified security settings I received an error message saying "Cannot create EJB instance. Nested message: null.". This message was not produced because of some of my business logic methods - the application ran fine before.

Here you find my ejb-jar.xml and ejb-j2ee-engine.xml files:

EJB:

===

<?xml version="1.0" encoding="UTF-8"?>

http://java.sun.com/dtd/ejb-jar_2_0.dtd">

<ejb-jar>

<description>EJBTest descr.</description>

<display-name>EJBTest</display-name>

<enterprise-beans>

<session>

<ejb-name>WDTestBean</ejb-name>

<home>de.hpi.WDTestHome</home>

<remote>de.hpi.WDTest</remote>

<local-home>de.hpi.WDTestLocalHome</local-home>

<local>de.hpi.WDTestLocal</local>

<ejb-class>de.hpi.WDTestBean</ejb-class>

<session-type>Stateless</session-type>

<transaction-type>Container</transaction-type>

<security-role-ref>

<role-name>administrator</role-name>

<role-link>wdtest</role-link>

</security-role-ref>

</session>

</enterprise-beans>

<assembly-descriptor>

<security-role>

<role-name>wdtest</role-name>

</security-role>

<method-permission>

<description>method-permission</description>

<role-name>wdtest</role-name>

<method>

<ejb-name>WDTestBean</ejb-name>

<method-name>*</method-name>

</method>

</method-permission>

</assembly-descriptor>

</ejb-jar>

===

J2EE:

===

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE ejb-j2ee-engine SYSTEM "ejb-j2ee-engine.dtd">

<ejb-j2ee-engine>

<enterprise-beans>

<enterprise-bean>

<ejb-name>WDTestBean</ejb-name>

<session-props/>

</enterprise-bean>

</enterprise-beans>

<security-permission>

<security-role-map>

<role-name>wdtest</role-name>

<server-role-name>rmsadmin</server-role-name>

</security-role-map>

</security-permission>

</ejb-j2ee-engine>

===

I really need your help on this topic - I have absolutely no clue why it doesn't work...

Thanks in advance!!

Regards,

H. Schubert