Oracle distributed transactions and Spring Framework

Does anyone know what the message (in red color) means? Why did I get the "not in transaction" error? I'm using SunOne App server and distributed transaction. If I configure the data source to use normal transaction, I won't see the warning message. Thanks.
---

2005-03-11 11:19:34,912 DEBUG OpenSessionInViewFilter:154 - Opening single Hibernate session in OpenSessionInViewFilter
2005-03-11 11:19:34,912 DEBUG SessionFactoryUtils:311 - Opening Hibernate session
2005-03-11 11:19:34,912 DEBUG TransactionSynchronizationManager:147 - Bound value [org.springframework.orm.hibernate.SessionHolder@19 d2bed] for key [net.sf.hibernate.impl.SessionFactoryImpl@1713b06] to thread [httpWorkerThread-8080-2]
2005-03-11 11:19:34,912 DEBUG DefaultListableBeanFactory:198 - Returning cached instance of singleton bean 'postingService'
2005-03-11 11:19:34,912 DEBUG DefaultListableBeanFactory:793 - Bean with name 'postingService' is a factory bean
2005-03-11 11:19:34,912 DEBUG TransactionSynchronizationManager:122 - Retrieved value [org.springframework.orm.hibernate.SessionHolder@19 d2bed] for key [net.sf.hibernate.impl.SessionFactoryImpl@1713b06] bound to thread [httpWorkerThread-8080-2]
2005-03-11 11:19:34,912 DEBUG TransactionSynchronizationManager:122 - Retrieved value [org.springframework.orm.hibernate.SessionHolder@19 d2bed] for key [net.sf.hibernate.impl.SessionFactoryImpl@1713b06] bound to thread [httpWorkerThread-8080-2]
2005-03-11 11:19:34,927 WARN SQLErrorCodeSQLExceptionTranslator:279 - Unable to translate SQLException with errorCode '17063', will now try the fallback translator
2005-03-11 11:19:34,927 INFO SQLStateSQLExceptionTranslator:70 - Translating SQLException with SQLState 'null' and errorCode '17063' and message [Not in a transaction]; SQL was [] for task [Hibernate operation]2005-03-11 11:19:34,927 DEBUG TransactionSynchronizationManager:122 - Retrieved value [org.springframework.orm.hibernate.SessionHolder@19 d2bed] for key [net.sf.hibernate.impl.SessionFactoryImpl@1713b06] bound to thread [httpWorkerThread-8080-2]
2005-03-11 11:19:35,021 DEBUG TransactionSynchronizationManager:170 - Removed value [org.springframework.orm.hibernate.SessionHolder@19 d2bed] for key [net.sf.hibernate.impl.SessionFactoryImpl@1713b06] from thread [httpWorkerThread-8080-2]
2005-03-11 11:19:35,021 DEBUG OpenSessionInViewFilter:179 - Closing single Hibernate session in OpenSessionInViewFilter
2005-03-11 11:19:35,021 DEBUG SessionFactoryUtils:649 - Closing Hibernate session

I have used the latest Sun app server, but are you sure that you're using the correct JDBC driver for distributed transactions? Spring drives distributed transactions using standard JTA UserTransaction calls, so please check Sun documentation to see if a special XA driver is required. It is in some app servers.