I don't know if this would help you, but I have this spring context configuration:
Also my application have persistence.xml in the META-INF folder, file which has the connection URL in my case. Which have this:
<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalEntityManagerFactoryBean">
<property name="persistenceUnitName" value="transactions-optional"/>
<bean name="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory"/>
I'm not a Spring expert however it shows that this is how things are wired together.
Also I found this just a while ago: