Exception possible nonthreadsafe access to session

I get this exception all the time: 14:30:54,578 ERROR http-8080-Processor25 http://localhost:8080/xwiki/bin/view/Main/WebHome AssertionFailure:<init>:22 - an assertion failure occured (this may indicate a bug in Hibernate, but is more likely due to unsafe use of the session) org.hibernate.AssertionFailure: possible nonthreadsafe access to session I should worry ? can i avoid that ? -- A.U.S. Enrique Ferreyra Centro de Cómputos Red Megatone - Red Confina