Erro : PrecoPorMetodo is not mapped [ FROM PrecoPorMetodo ]

Front-end
#1 
		PrecoPorMetodoBean osb = new PrecoPorMetodoBean();
		List<PrecoPorMetodo> resultado1 = osb.selecionaprecopormetodo(metodo.getId().toString());



public class PrecoPorMetodoBean {
    public List<PrecoPorMetodo> selecionaprecopormetodo(String vMetodo_id) {
        try {
        	
      	   EntityManagerFactory factory= Persistence.createEntityManagerFactory("lims-pu");
     	   EntityManager manager= factory.createEntityManager();
    
			StringBuffer sbQuery = new StringBuffer();
			sbQuery.append(" FROM PrecoPorMetodo ");			
***********************************aqui esta o erro 		****************************************
			Query query = manager.createQuery(sbQuery.toString());
			return query.getResultList();	
        	
        }
        catch (Throwable ex) {             
            System.err.println("failed.----" + ex);  
            throw new ExceptionInInitializerError(ex);  
        }     	   	
    }   	
}


persistence.xml

<persistence xmlns="http://java.sun.com/xml/ns/persistence"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://java.sun.com/xml/ns/persistence
    http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd"
	version="1.0">
	<persistence-unit name="lims-pu"  transaction-type="JTA">
	<provider>org.hibernate.ejb.HibernatePersistence</provider>
	
		<jta-data-source>java:/LimsDS</jta-data-source>
		<jar-file>../auditor-ejb-${pom.version}.jar</jar-file>
		<jar-file>../usuario-ejb-${pom.version}.jar</jar-file>
		<jar-file>../funcionario-ejb-${pom.version}.jar</jar-file>
		<jar-file>../cliente-ejb-${pom.version}.jar</jar-file>
		<jar-file>../orcamento-ejb-${pom.version}.jar</jar-file>
		<jar-file>../comum-ejb-${pom.version}.jar</jar-file>
		<jar-file>../analise-ejb-${pom.version}.jar</jar-file>
		<jar-file>../coleta-ejb-${pom.version}.jar</jar-file>
		<jar-file>../faturamento-ejb-${pom.version}.jar</jar-file>
		<jar-file>../laudo-ejb-${pom.version}.jar</jar-file>



		<properties>

				<property name="hibernate.transaction.manager_lookup_class"  
 value="org.hibernate.transaction.JBossTransactionManagerLookup"/> 

		
			<property name="hibernate.dialect" value="${hibernate.dialect}" />
			<!-- property name="hibernate.hbm2ddl.auto" value="${hibernate.hbm2ddl}" /-->
			<property name="hibernate.show_sql" value="${hibernate.show_sql}" />

			<property name="hibernate.cache.provider_class" value="${hibernate.cache.provider_class}"/>
			<property name="hibernate.cache.use_second_level_cache" value="${hibernate.cache.use_second_level_cache}"/>
			<property name="hibernate.cache.use_query_cache" value="${hibernate.cache.use_query_cache}"/>
			<property name="hibernate.jdbc.batch_size" value="0" />

		</properties>
	</persistence-unit>
</persistence>

OBS : Esta minha classe esta dentro do …/orcamento-ejb-${pom.version}.jar

Pq iria dar erro de mapeamento se a minha classe esta dentro de …/orcamento-ejb-${pom.version}.jar???
ERRO:
org.hibernate.hql.ast.QuerySyntaxException: PrecoPorMetodo is not mapped [ FROM PrecoPorMetodo ]

#2