Context [/petclinic] startup failed due to previous errors

Hi Im getting the following error when trying to deploy the petclinic application to tomcat:
in locahost.log
Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListe ner
java.lang.NoClassDefFoundError: Ljavax/transaction/TransactionManager;
at java.lang.Class.getDeclaredFields0(Native Method)
at java.lang.Class.privateGetDeclaredFields(Class.jav a:2291)
at java.lang.Class.getDeclaredFields(Class.java:1743)

catalina.log
Oct 3, 2012 5:12:19 PM org.apache.catalina.core.StandardContext start
SEVERE: Error listenerStart
Oct 3, 2012 5:12:19 PM org.apache.catalina.core.StandardContext start
SEVERE: Context [/petclinic] startup failed due to previous errors

I have added the org.springframework.instrument.tomcat-3.0.0.RELEASE to tomcat libs and Im using the following environment.

Mac OSX Lion 10.7
Tomcat 6
MySQL 5
Spring 3
Hibernate 3
Eclipse Juno

What is the reason for this and what can I do to fix it?