Hibernate version: 3.2.2.ga
Hibernate annotation/entity manager: 3.2.1.ga

Note: I have two projects; the common code in one jar file, and the project I am working on (a webapp), which contains the persistence.xml.

persistence.xml:
<?xml version='1.0'?>
<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/ ... ce_1_0.xsd" version="1.0">
<persistence-unit name="default">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<jar-file>WEB-INF/lib/xware-common-2.0-SNAPSHOT.jar</jar-file>
</persistence-unit>
</persistence>

The problem(s):
The first problem, while annoying, is at least fixable. When using junit and Hibernate/JPA, I had to hardcode the link to the jar-file reference, otherwise it will not find it on the classpath. Is there a way to get that to work, so that I don't need to keep hacking the persistence file for use with JUnit, and then fixing it for deployment?

The second problem is the one I have not found a workaround for. When I do change the persistence.xml jar-file mapping to hardcode the link to the library, the entity manager no longer sees the annotated classes in the project with the unit tests. How can I fix that?

Have you considered filtering your persistence.xml during the build? I normally use maven as build tool and resources like persistence.xml or data source definitions I filter using maven's filter functionality (http://maven.apache.org/guides/getting-started/index.html#How_do_I_filter_resource_files). Depending on the environment I am building for different values get filtered into the resource files. Ant offers filtering as well of course.

When you are mentioning JUnit - how do you set your tests up? Do you use pure junit? If you for example also use Spring in your web application you could use abstractJpaTests ( http://static.springframework.org/spring/docs/2.5.x/api/org/springframework/test/jpa/AbstractJpaTests.html.