Spring, Hibernate & JPA: Calling persist on entitymanager does not seem to commit to database

<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource">
    <property name="url" value="${jdbc.url}"/>
    <property name="driverClassName" value="${jdbc.driverClassName}"/>
    <property name="username" value="${jdbc.username}"/>
    <property name="password" value="${jdbc.password}"/>
</bean>

<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
	<property name="dataSource" ref="dataSource" />
	<property name="persistenceUnitName" value="BankingWeb" />
	<property name="jpaVendorAdapter">
		<bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
			<property name="generateDdl" value="true" />
			<property name="showSql" value="true" />
			<property name="databasePlatform" value="${hibernate.dialect}" />
		</bean>
	</property>
</bean>

<tx:annotation-driven/>

<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
    <property name="entityManagerFactory" ref="entityManagerFactory"/>
</bean>

<bean class="org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor" />

<bean class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor"/>

<bean name="accountManager" class="ssel.banking.dao.jpa.AccountManager" />
<bean name="userManager" class="ssel.banking.dao.jpa.UserManager" />

@Repository
public class AccountManager implements IAccountManager {

    @PersistenceContext private EntityManager em;

    /* -- 8< -- Query methods omitted -- 8< -- */

    public Account storeAccount(Account ac) {
	ac = em.merge(ac);
    	em.persist(ac);
    	return ac;
    }
}

Account ac = new Account();
	ac.setId(mostRecent.getId()+1);
	ac.setUser(user);
	ac.setName(accName);
	ac.setDate(new Date());
	ac.setValue(0);
	ac = accountManager.storeAccount(ac);
	return ac;

@SuppressWarnings("serial")
@Entity
@NamedQueries({
		@NamedQuery(name = "Account.AllAccounts", query = "SELECT a FROM Account a"),
		@NamedQuery(name = "Account.Accounts4User", query = "SELECT a FROM Account a WHERE user=:user"),
		@NamedQuery(name = "Account.Account4Name", query = "SELECT a FROM Account a WHERE name=:name"),
		@NamedQuery(name = "Account.MaxId", query = "SELECT MAX(a.id) FROM Account a"),
		@NamedQuery(name = "Account.Account4Id", query = "SELECT a FROM Account a WHERE id=:id"),
	})
public class Account extends AbstractNamedDomain {
	@Temporal(TemporalType.DATE)
	@Column(name = "xdate")
	private Date date;

	private double value;

	@ManyToOne(cascade={CascadeType.PERSIST, CascadeType.MERGE})
	@JoinColumn(name="userid")
	private User user;

	public User getUser() {
		return user;
	}

	public void setUser(User user) {
		this.user = user;
	}

	@OneToMany(cascade={CascadeType.PERSIST, CascadeType.MERGE}, fetch=FetchType.EAGER)
	@OrderBy("date")
	private List<AccountActivity> accountActivity = new ArrayList<AccountActivity>();

	public List<AccountActivity> getAccountActivity() {
		return accountActivity;
	}

	public void setAccountActivity(List<AccountActivity> accountActivity) {
		this.accountActivity = accountActivity;
	}

	public Date getDate() {
		return date;
	}

	public void setDate(Date date) {
		this.date = date;
	}

	public double getValue() {
		return value;
	}

	public void setValue(double value) {
		this.value = value;
	}

	public void addAccountActivity(AccountActivity activity) {
		// Make sure ordering is maintained, JPA only does this on loading
		int i = 0;
		while (i < getAccountActivity().size()) {
			if (getAccountActivity().get(i).getDate().compareTo(activity.getDate()) <= 0)
				break;
			i++;
		}
		getAccountActivity().add(i, activity);
	}
}

@MappedSuperclass public abstract class AbstractNamedDomain extends AbstractDomain {

	private String name;

	public AbstractNamedDomain() {

	}

	public AbstractNamedDomain(String name) {

		this.name = name;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}
}

@MappedSuperclass public abstract class AbstractDomain implements Serializable {

	@Id @GeneratedValue
	private long id = NEW_ID;

	public static long NEW_ID = -1;

	public long getId() {
		return id;
	}

	public void setId(long id) {
		this.id = id;
	}

	public boolean isNew() {

		return id==NEW_ID;
	}
}

@TransactionManagement(TransactionManagementType.BEAN)
public class AccountManager implements IAccountManager { ..}

@Resource
private SessionContext sessionContext;

public Account storeAccount(Account ac) {
    sessionContext.getUserTransaction().begin();
    ac = em.merge(ac);
    em.persist(ac);
    sessionContext.getUserTransaction().commit();
    return ac;
}