[pbrewer_uk]

Thanks Pete, I have now filled a JIRA relating to this issue. I've also done some further investigation and discovered that JBPM session is not null.

The NPE is caused by a call to getTransactionManager().getTransaction() in Hibernates JTATransaction class that returns null. Its detailed in the jira issue:
http://jira.jboss.org/jira/browse/JBSEAM-2575

I'll post in the jbpm forum shortly.

BTW
Please ignore the previous post about a possible related error "uninitialized proxy passed to save". I was accessing the jbpm context in a strange way. For some reason, I was calling:

JbpmContext jbpmContext = Jbpm.instance().getJbpmConfiguration().createJbpmContext() ;

instead of:

@In JbpmContext jbpmContext;

[pbrewer_uk]

I've added an example ear and project source to the jira

And I've now posted on the jBPM forums too:
http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4126208#4126208

[torsty]

hi, have you solved your problem? I did something similar with seam 2.0.1GA and jbpm 3.2.2.

Everything worked all right. process-definition looked like:

<process-definition
 name="myWf"
 xmlns="urn:jbpm.org:jpdl-3.2"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="urn:jbpm.org:jpdl-3.2 http://jbpm.org/xsd/jpdl-3.2.xsd">

 <start-state name="start" >
 <transition to="step1"/>
 </start-state>

 <task-node name="step1" end-tasks="true">
 <event type="node-enter">
 <create-timer name="myTimeout" duedate="30 seconds" transition="toExpire">
 <action name="testWriteOut" expression="#{timerLogger.logTimer}"/>
 </create-timer>
 </event>
 <task name="stepOneTask" description="task 1">
 <assignment actor-id="#{currentUser.id}" />
 </task>
 <transition name="finished" to="end"/>
 <transition name="toExpire" to="expire"/>
 </task-node>
...

The action I call looks like:

package my.package;

import java.io.Serializable;

import org.jboss.seam.ScopeType;
import org.jboss.seam.annotations.End;
import org.jboss.seam.annotations.In;
import org.jboss.seam.annotations.Logger;
import org.jboss.seam.annotations.Name;
import org.jboss.seam.annotations.Scope;
import org.jboss.seam.log.Log;

@Name( "timerLogger" )
@Scope( ScopeType.CONVERSATION )
public class TimerLogger implements Serializable {
 /**
 *
 */
 private static final long serialVersionUID = 6974693306545880498L;

 @Logger
 private Log log;

 @In(value="aContextVariable", scope=ScopeType.BUSINESS_PROCESS)
 String aContextVariable; // this is a business process context variable

 @End
 public void logTimer( )
 {
 System.out.println( "---------------- timer was created." );
 log.info( "--------- variable: " + aContextVariable );
 }
}

My jbpm.cfg.xml looks like:

<jbpm-configuration>

 <jbpm-context>
 <service name="persistence">
 <factory>
 <bean class="org.jbpm.persistence.db.DbPersistenceServiceFactory">
 <field name="isTransactionEnabled"><false/></field>
 </bean>
 </factory>
 </service>
 <service name="tx" factory="org.jbpm.tx.TxServiceFactory" />
 <service name="message" factory="org.jbpm.msg.db.DbMessageServiceFactory" />
 <service name="scheduler" factory="org.jbpm.scheduler.db.DbSchedulerServiceFactory"/>
 <!-- <service name="scheduler" factory="org.jbpm.scheduler.ejbtimer.EjbSchedulerServiceFactory" />-->
 <service name="logging" factory="org.jbpm.logging.db.DbLoggingServiceFactory" />
 <service name="authentication" factory="org.jbpm.security.authentication.DefaultAuthenticationServiceFactory" />
 </jbpm-context>

 <!-- configuration property used by persistence service impl org.jbpm.persistence.db.DbPersistenceServiceFactory -->
 <string name="resource.hibernate.cfg.xml" value="hibernate.cfg.xml" />

 <!-- configuration resource files pointing to default configuration files in jbpm-jpdl.jar -->
 <string name="resource.business.calendar" value="org/jbpm/calendar/jbpm.business.calendar.properties" />
 <string name="resource.default.modules" value="org/jbpm/graph/def/jbpm.default.modules.properties" />
 <string name="resource.converter" value="org/jbpm/db/hibernate/jbpm.converter.properties" />
 <string name="resource.action.types" value="org/jbpm/graph/action/action.types.xml" />
 <string name="resource.node.types" value="org/jbpm/graph/node/node.types.xml" />
 <string name="resource.parsers" value="org/jbpm/jpdl/par/jbpm.parsers.xml" />
 <string name="resource.varmapping" value="org/jbpm/context/exe/jbpm.varmapping.xml" />
 <string name="resource.mail.templates" value="jbpm.mail.templates.xml" />

 <int name="jbpm.byte.block.size" value="1024" singleton="true" />
 <string name="jbpm.mail.smtp.host" value="localhost" />
 <bean name="jbpm.task.instance.factory" class="org.jbpm.taskmgmt.impl.DefaultTaskInstanceFactoryImpl" singleton="true" />
 <bean name="jbpm.variable.resolver" class="org.jbpm.jpdl.el.impl.JbpmVariableResolver" singleton="true" />
 <bean name="jbpm.mail.address.resolver" class="org.jbpm.identity.mail.IdentityAddressResolver" singleton="true" />

 <!-- note that the default job executor needs to be overwritten with a null value -->
 <!-- <null name="jbpm.job.executor" /> -->


</jbpm-configuration>

I am using the JobExecutor Servlet in web.xml

 <servlet>
 <servlet-name>JobExecutorServlet</servlet-name>
 <servlet-class>org.jbpm.job.executor.JobExecutorServlet</servlet-class>
 <load-on-startup>1</load-on-startup>
 </servlet>
 <servlet-mapping>
 <servlet-name>JobExecutorServlet</servlet-name>
 <url-pattern>/jobs</url-pattern>
 </servlet-mapping>

Hoping it helps a little bit.