Please please help me,
I am using JBoss Jbpm and hibernate and I keep getting this exception: No data type for node: Exception in thread "main" java.lang.IllegalStateException: No data type for node: org.hibernate.hql.ast.tree.MethodNode
\-[METHOD_CALL] MethodNode: '('
+-[METHOD_NAME] IdentNode: 'stddev' {originalText=stddev}
\-[EXPR_LIST] SqlNode: 'exprList'
\-[DOT] DotNode: 'nodelog0_.DURATION_' {propertyName=duration,dereferenceType=ALL,propertyPath=duration,path=nl.duration,tableAlias=nodelog0_,className=org.jbpm.graph.log.NodeLog,classAlias=nl}
+-[ALIAS_REF] IdentNode: 'nodelog0_.ID_' {alias=nl, className=org.jbpm.graph.log.NodeLog, tableAlias=nodelog0_}
\-[IDENT] IdentNode: 'duration' {originalText=duration}

at org.hibernate.hql.ast.tree.SelectClause.initializeExplicitSelectClause(SelectClause.java:156)
at org.hibernate.hql.ast.HqlSqlWalker.useSelectClause(HqlSqlWalker.java:857)
at org.hibernate.hql.ast.HqlSqlWalker.processQuery(HqlSqlWalker.java:645)
at org.hibernate.hql.antlr.HqlSqlBaseWalker.query(HqlSqlBaseWalker.java:685)
at org.hibernate.hql.antlr.HqlSqlBaseWalker.selectStatement(HqlSqlBaseWalker.java:301)
at org.hibernate.hql.antlr.HqlSqlBaseWalker.statement(HqlSqlBaseWalker.java:244)
at org.hibernate.hql.ast.QueryTranslatorImpl.analyze(QueryTranslatorImpl.java:256)
at org.hibernate.hql.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:187)
at org.hibernate.hql.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:138)
at org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:101)
at org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:80)
at org.hibernate.engine.query.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:124)
at org.hibernate.impl.SessionFactoryImpl.checkNamedQueries(SessionFactoryImpl.java:549)
at org.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java:413)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1872)
at org.jbpm.persistence.db.DbPersistenceServiceFactory.getSessionFactory(DbPersistenceServiceFactory.java:104)
at org.jbpm.persistence.db.DbPersistenceService.getSessionFactory(DbPersistenceService.java:84)
at org.jbpm.persistence.db.DbPersistenceService.getSession(DbPersistenceService.java:89)
at org.jbpm.persistence.db.DbPersistenceService.getGraphSession(DbPersistenceService.java:320)
at org.jbpm.JbpmContext.getGraphSession(JbpmContext.java:604)
at org.jbpm.command.GetProcessDefinitionCommand.execute(GetProcessDefinitionCommand.java:37)
at org.jbpm.sim.bam.GetSimulationInputCommand.execute(GetSimulationInputCommand.java:69)
at CreateHistoricalData.runMySQL(CreateHistoricalData.java:104)
at CreateHistoricalData.main(CreateHistoricalData.java:43)